docs: add Factorial

release v1.2.6
test: add TestTruncRound
2026-02-04 12:52:28 +08:00 · 2022-03-04 17:37:49 +08:00 · 2022-03-04 17:31:38 +08:00 · 2022-03-04 17:30:47 +08:00 · 2022-03-04 17:28:53 +08:00 · 2022-03-03 15:55:36 +08:00
30 changed files with 1877 additions and 48 deletions
--- a/README.md
+++ b/README.md
@@ -1,24 +1,30 @@
-# Lancet
-<p style="font-size: 18px"> 
-    Lancet is a comprehensive, efficient, and reusable util function library of go. Inspired by the java apache common package and lodash.js.
-</p>
+<div align=center>
+<img src="./logo.png" width="200" height="200"/>
+
+<br/>

 ![Go version](https://img.shields.io/badge/go-%3E%3D1.16<recommend>-9cf)
-[![Release](https://img.shields.io/badge/release-1.2.3-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-1.2.6-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com//duke-git/lancet?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet)](https://goreportcard.com/report/github.com/duke-git/lancet)
 [![test](https://github.com/duke-git/lancet/actions/workflows/codecov.yml/badge.svg?branch=main&event=push)](https://github.com/duke-git/lancet/actions/workflows/codecov.yml)
 [![codecov](https://codecov.io/gh/duke-git/lancet/branch/main/graph/badge.svg?token=FC48T1F078)](https://codecov.io/gh/duke-git/lancet)
 [![License](https://img.shields.io/badge/license-MIT-blue.svg)](https://github.com/duke-git/lancet/blob/main/LICENSE)

+</div>
+
+<div STYLE="page-break-after: always;"></div>
+
+<p style="font-size: 20px"> 
+    Lancet is a comprehensive, efficient, and reusable util function library of go. Inspired by the java apache common package and lodash.js.
+</p>

 English | [简体中文](./README_zh-CN.md)

-
 ## Feature

 - 👏 Comprehensive, efficient and reusable.
- 💪 160+ common go util functions, support string, slice, datetime, net, crypt...
+- 💪 180+ go util functions, support string, slice, datetime, net, crypt...
 - 💅 Only depend on the go standard library.
 - 🌍 Unit test for every exported function.

@@ -122,6 +128,18 @@ import "github.com/duke-git/lancet/datetime"
 - [AddDay](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#AddDay)
 - [AddHour](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#AddHour)
 - [AddMinute](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#AddMinute)
+- [BeginOfMinute](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfMinute)
+- [BeginOfHour](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfHour)
+- [BeginOfDay](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfDay)
+- [BeginOfWeek](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfWeek)
+- [BeginOfMonth](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfMonth)
+- [BeginOfYear](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfYear)
+- [EndOfMinute](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfMinute)
+- [EndOfHour](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfHour)
+- [EndOfDay](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfDay)
+- [EndOfWeek](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfWeek)
+- [EndOfMonth](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfMonth)
+- [EndOfYear](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfYear)
 - [GetNowDate](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#GetNowDate)
 - [GetNowTime](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#GetNowTime)
 - [GetNowDateTime](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#GetNowDateTime)
@@ -156,9 +174,7 @@ import "github.com/duke-git/lancet/fileutil"
 ### Formatter contains some functions for data formatting.

 ```go
-import (
-    "github.com/duke-git/lancet/formatter"
-)
+import "github.com/duke-git/lancet/formatter"
 ```
 #### Function list:
 - [Comma](https://github.com/duke-git/lancet/blob/main/docs/formatter.md#Comma)
@@ -176,9 +192,25 @@ import "github.com/duke-git/lancet/function"
 - [Compose](https://github.com/duke-git/lancet/blob/main/docs/function.md#Compose)
 - [Debounced](https://github.com/duke-git/lancet/blob/main/docs/function.md#Debounced)
 - [Delay](https://github.com/duke-git/lancet/blob/main/docs/function.md#Delay)
- [Delay](https://github.com/duke-git/lancet/blob/main/docs/function.md#Delay)
 - [Watcher](https://github.com/duke-git/lancet/blob/main/docs/function.md#Watcher)

+
+### Mathutil package implements some functions for math calculation.
+
+```go
+import "github.com/duke-git/lancet/mathutil"
+```
+
+#### Function list:
+- [Exponent](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#Exponent)
+- [Fibonacci](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#Fibonacci)
+- [Factorial](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#Factorial)
+- [Percent](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#Percent)
+- [RoundToFloat](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#RoundToFloat)
+- [RoundToString](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#RoundToString)
+- [TruncRound](https://github.com/duke-git/lancet/blob/main/docs/mathutil.md#TruncRound)
+
+
 ### Netutil package contains functions to get net information and send http request.

 ```go
@@ -188,6 +220,8 @@ import "github.com/duke-git/lancet/netutil"
 #### Function list:
 - [ConvertMapToQueryString](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#ConvertMapToQueryString)
 - [GetInternalIp](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#GetInternalIp)
+- [GetIps](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#GetIps)
+- [GetMacAddrs](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#GetMacAddrs)
 - [GetPublicIpInfo](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#GetPublicIpInfo)
 - [IsPublicIP](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#IsPublicIP)
 - [HttpGet](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#HttpGet)
@@ -207,6 +241,7 @@ import "github.com/duke-git/lancet/random"
 - [RandBytes](https://github.com/duke-git/lancet/blob/main/docs/random.md#RandBytes)
 - [RandInt](https://github.com/duke-git/lancet/blob/main/docs/random.md#RandInt)
 - [RandString](https://github.com/duke-git/lancet/blob/main/docs/random.md#RandString)
+- [UUIdV4](https://github.com/duke-git/lancet/blob/main/docs/random.md#UUIdV4)

 ### Retry package is for executing a function repeatedly until it was successful or canceled by the context.

@@ -334,4 +369,15 @@ import "github.com/duke-git/lancet/validator"
 - [IsIpV6](https://github.com/duke-git/lancet/blob/main/docs/validator.md#IsIpV6)
 - [IsStrongPassword](https://github.com/duke-git/lancet/blob/main/docs/validator.md#IsStrongPassword)
 - [IsUrl](https://github.com/duke-git/lancet/blob/main/docs/validator.md#IsUrl)
- [IsWeakPassword](https://github.com/duke-git/lancet/blob/main/docs/validator.md#IsWeakPassword)
+- [IsWeakPassword](https://github.com/duke-git/lancet/blob/main/docs/validator.md#IsWeakPassword)
+  
+
+## How to Contribute
+
+I really appreciate any code commits which make lancet lib powerful. Please follow the rules below to create your pull request.
+
+1. Fork the repository.
+2. Create your feature branch.
+3. Commit your changes.
+4. Push to the branch
+5. Create new pull request.
--- a/README_zh-CN.md
+++ b/README_zh-CN.md
@@ -1,16 +1,22 @@
-# Lancet
-<p style="font-size: 18px">
-    lancet（柳叶刀）是一个全面、高效、可复用的go语言工具函数库。 lancet受到了java apache common包和lodash.js的启发。
-</p>
+<div align=center>
+<img src="./logo.png" width="200" height="200"/>
+
+<br/>

 ![Go version](https://img.shields.io/badge/go-%3E%3D1.16<recommend>-9cf)
-[![Release](https://img.shields.io/badge/release-1.2.3-green.svg)](https://github.com/duke-git/lancet/releases)
+[![Release](https://img.shields.io/badge/release-1.2.6-green.svg)](https://github.com/duke-git/lancet/releases)
 [![GoDoc](https://godoc.org/github.com//duke-git/lancet?status.svg)](https://pkg.go.dev/github.com/duke-git/lancet)
 [![Go Report Card](https://goreportcard.com/badge/github.com/duke-git/lancet)](https://goreportcard.com/report/github.com/duke-git/lancet)
 [![test](https://github.com/duke-git/lancet/actions/workflows/codecov.yml/badge.svg?branch=main&event=push)](https://github.com/duke-git/lancet/actions/workflows/codecov.yml)
 [![codecov](https://codecov.io/gh/duke-git/lancet/branch/main/graph/badge.svg?token=FC48T1F078)](https://codecov.io/gh/duke-git/lancet)
 [![License](https://img.shields.io/badge/license-MIT-blue.svg)](https://github.com/duke-git/lancet/blob/main/LICENSE)

+</div>
+
+<div STYLE="page-break-after: always;"></div>
+<p style="font-size: 18px">
+    lancet（柳叶刀）是一个全面、高效、可复用的go语言工具函数库。 lancet受到了java apache common包和lodash.js的启发。
+</p>

 简体中文 | [English](./README.md)

@@ -18,7 +24,7 @@
 ## 特性

 - 👏 全面、高效、可复用
- 💪 170+常用go工具函数，支持string、slice、datetime、net、crypt...
+- 💪 180+常用go工具函数，支持string、slice、datetime、net、crypt...
 - 💅 只依赖go标准库
 - 🌍 所有导出函数单元测试覆盖率100%

@@ -122,6 +128,18 @@ import "github.com/duke-git/lancet/datetime"
 - [AddDay](https://github.com/duke-git/lancet/blob/main/docs/datetime_zh-CN.md#AddDay)
 - [AddHour](https://github.com/duke-git/lancet/blob/main/docs/datetime_zh-CN.md#AddHour)
 - [AddMinute](https://github.com/duke-git/lancet/blob/main/docs/datetime_zh-CN.md#AddMinute)
+- [BeginOfMinute](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfMinute)
+- [BeginOfHour](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfHour)
+- [BeginOfDay](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfDay)
+- [BeginOfWeek](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfWeek)
+- [BeginOfMonth](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfMonth)
+- [BeginOfYear](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#BeginOfYear)
+- [EndOfMinute](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfMinute)
+- [EndOfHour](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfHour)
+- [EndOfDay](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfDay)
+- [EndOfWeek](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfWeek)
+- [EndOfMonth](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfMonth)
+- [EndOfYear](https://github.com/duke-git/lancet/blob/main/docs/datetime.md#EndOfYear)
 - [GetNowDate](https://github.com/duke-git/lancet/blob/main/docs/datetime_zh-CN.md#GetNowDate)
 - [GetNowTime](https://github.com/duke-git/lancet/blob/main/docs/datetime_zh-CN.md#GetNowTime)
 - [GetNowDateTime](https://github.com/duke-git/lancet/blob/main/docs/datetime_zh-CN.md#GetNowDateTime)
@@ -156,9 +174,7 @@ import "github.com/duke-git/lancet/fileutil"
 ### formatter格式化器包含一些数据格式化处理方法。

 ```go
-import (
-    "github.com/duke-git/lancet/formatter"
-)
+import "github.com/duke-git/lancet/formatter"
 ```
 #### 函数列表:
 - [Comma](https://github.com/duke-git/lancet/blob/main/docs/formatter_zh-CN.md#Comma)
@@ -177,9 +193,22 @@ import "github.com/duke-git/lancet/function"
 - [Compose](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Compose)
 - [Debounced](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Debounced)
 - [Delay](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Delay)
- [Delay](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Delay)
 - [Watcher](https://github.com/duke-git/lancet/blob/main/docs/function_zh-CN.md#Watcher)

+### mathutil包实现了一些数学计算的函数。
+
+```go
+import "github.com/duke-git/lancet/mathutil"
+```
+
+#### Function list:
+- [Exponent](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#Exponent)
+- [Fibonacci](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#Fibonacci)
+- [Factorial](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#Factorial)
+- [Percent](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#Percent)
+- [RoundToFloat](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#RoundToFloat)
+- [RoundToString](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#RoundToString)
+- [TruncRound](https://github.com/duke-git/lancet/blob/main/docs/mathutil_zh-CN.md#TruncRound)

 ### netutil网络包支持获取ip地址，发送http请求。

@@ -190,6 +219,8 @@ import "github.com/duke-git/lancet/netutil"
 #### 函数列表:
 - [ConvertMapToQueryString](https://github.com/duke-git/lancet/blob/main/docs/netutil_zh-CN.md#ConvertMapToQueryString)
 - [GetInternalIp](https://github.com/duke-git/lancet/blob/main/docs/netutil_zh-CN.md#GetInternalIp)
+- [GetIps](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#GetIps)
+- [GetMacAddrs](https://github.com/duke-git/lancet/blob/main/docs/netutil.md#GetMacAddrs)
 - [GetPublicIpInfo](https://github.com/duke-git/lancet/blob/main/docs/netutil_zh-CN.md#GetPublicIpInfo)
 - [IsPublicIP](https://github.com/duke-git/lancet/blob/main/docs/netutil_zh-CN.md#IsPublicIP)
 - [HttpGet](https://github.com/duke-git/lancet/blob/main/docs/netutil_zh-CN.md#HttpGet)
@@ -209,7 +240,7 @@ import "github.com/duke-git/lancet/random"
 - [RandBytes](https://github.com/duke-git/lancet/blob/main/docs/random_zh-CN.md#RandBytes)
 - [RandInt](https://github.com/duke-git/lancet/blob/main/docs/random_zh-CN.md#RandInt)
 - [RandString](https://github.com/duke-git/lancet/blob/main/docs/random_zh-CN.md#RandString)
-
+- [UUIdV4](https://github.com/duke-git/lancet/blob/main/docs/random.md#UUIdV4)
 ### retry重试执行函数直到函数运行成功或被context cancel。

 ```go
@@ -339,4 +370,15 @@ import "github.com/duke-git/lancet/validator"
 - [IsIpV6](https://github.com/duke-git/lancet/blob/main/docs/validator_zh-CN.md#IsIpV6)
 - [IsStrongPassword](https://github.com/duke-git/lancet/blob/main/docs/validator_zh-CN.md#IsStrongPassword)
 - [IsUrl](https://github.com/duke-git/lancet/blob/main/docs/validator_zh-CN.md#IsUrl)
- [IsWeakPassword](https://github.com/duke-git/lancet/blob/main/docs/validator_zh-CN.md#IsWeakPassword)
+- [IsWeakPassword](https://github.com/duke-git/lancet/blob/main/docs/validator_zh-CN.md#IsWeakPassword)
+
+
+## 如何贡献代码
+
+非常感激任何的代码提交以使lancet的功能越来越强大。创建pull request时请遵守以下规则。
+
+1. Fork lancet仓库。
+2. 创建自己的特性分支。
+3. 提交变更。
+4. Push分支。
+5. 创建新的pull request。
--- a/cryptor/crypto_internal.go
+++ b/cryptor/crypto_internal.go
--- a/datetime/datetime.go
+++ b/datetime/datetime.go
@@ -110,3 +110,73 @@ func FormatStrToTime(str, format string) (time.Time, error) {

 	return time.Parse(v, str)
 }
+
+// BeginOfMinute return beginning minute time of day
+func BeginOfMinute(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, t.Hour(), t.Minute(), 0, 0, t.Location())
+}
+
+// EndOfMinute return end minute time of day
+func EndOfMinute(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, t.Hour(), t.Minute(), 59, int(time.Second-time.Nanosecond), t.Location())
+}
+
+// BeginOfHour return beginning hour time of day
+func BeginOfHour(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, t.Hour(), 0, 0, 0, t.Location())
+}
+
+// EndOfHour return end hour time of day
+func EndOfHour(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, t.Hour(), 59, 59, int(time.Second-time.Nanosecond), t.Location())
+}
+
+// BeginOfDay return beginning hour time of day
+func BeginOfDay(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, 0, 0, 0, 0, t.Location())
+}
+
+// EndOfDay return end time of day
+func EndOfDay(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, 23, 59, 59, int(time.Second-time.Nanosecond), t.Location())
+}
+
+// BeginOfWeek return beginning week, week begin from Sunday
+func BeginOfWeek(t time.Time) time.Time {
+	y, m, d := t.AddDate(0, 0, 0-int(BeginOfDay(t).Weekday())).Date()
+	return time.Date(y, m, d, 0, 0, 0, 0, t.Location())
+}
+
+// EndOfWeek return end week time, week end with Saturday
+func EndOfWeek(t time.Time) time.Time {
+	y, m, d := BeginOfWeek(t).AddDate(0, 0, 7).Add(-time.Nanosecond).Date()
+	return time.Date(y, m, d, 23, 59, 59, int(time.Second-time.Nanosecond), t.Location())
+}
+
+// BeginOfMonth return beginning of month
+func BeginOfMonth(t time.Time) time.Time {
+	y, m, _ := t.Date()
+	return time.Date(y, m, 1, 0, 0, 0, 0, t.Location())
+}
+
+// EndOfMonth return end of month
+func EndOfMonth(t time.Time) time.Time {
+	return BeginOfMonth(t).AddDate(0, 1, 0).Add(-time.Nanosecond)
+}
+
+// BeginOfYear return beginning of year
+func BeginOfYear(t time.Time) time.Time {
+	y, _, _ := t.Date()
+	return time.Date(y, time.January, 1, 0, 0, 0, 0, t.Location())
+}
+
+// EndOfYear return end of year
+func EndOfYear(t time.Time) time.Time {
+	return BeginOfYear(t).AddDate(1, 0, 0).Add(-time.Nanosecond)
+}
--- a/datetime/datetime_test.go
+++ b/datetime/datetime_test.go
@@ -64,16 +64,6 @@ func TestGetNowDateTime(t *testing.T) {
 	assert.Equal(expected, GetNowDateTime())
 }

-//todo
-//func TestGetZeroHourTimestamp(t *testing.T) {
-//	ts := GetZeroHourTimestamp()
-//	expected := time.Now().UTC().Unix() - 8*3600
-//	if ts != expected {
-//		utils.LogFailedTestInfo(t, "GetZeroHourTimestamp", "", expected, ts)
-//		t.FailNow()
-//	}
-//}
-
 func TestFormatTimeToStr(t *testing.T) {
 	assert := internal.NewAssert(t, "TestFormatTimeToStr")

@@ -121,3 +111,123 @@ func TestFormatStrToTime(t *testing.T) {
 		assert.Equal(expected, actual)
 	}
 }
+
+func TestBeginOfMinute(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBeginOfMinute")
+
+	expected := time.Date(2022, 2, 15, 15, 48, 0, 0, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := BeginOfMinute(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestEndOfMinute(t *testing.T) {
+	assert := internal.NewAssert(t, "TestEndOfMinute")
+
+	expected := time.Date(2022, 2, 15, 15, 48, 59, 999999999, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := EndOfMinute(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestBeginOfHour(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBeginOfHour")
+
+	expected := time.Date(2022, 2, 15, 15, 0, 0, 0, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := BeginOfHour(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestEndOfHour(t *testing.T) {
+	assert := internal.NewAssert(t, "TestEndOfHour")
+
+	expected := time.Date(2022, 2, 15, 15, 59, 59, 999999999, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := EndOfHour(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestBeginOfDay(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBeginOfDay")
+
+	expected := time.Date(2022, 2, 15, 0, 0, 0, 0, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := BeginOfDay(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestEndOfDay(t *testing.T) {
+	assert := internal.NewAssert(t, "TestEndOfDay")
+
+	expected := time.Date(2022, 2, 15, 23, 59, 59, 999999999, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := EndOfDay(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestBeginOfWeek(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBeginOfWeek")
+
+	expected := time.Date(2022, 2, 13, 0, 0, 0, 0, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := BeginOfWeek(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestEndOfWeek(t *testing.T) {
+	assert := internal.NewAssert(t, "TestEndOfWeek")
+
+	expected := time.Date(2022, 2, 19, 23, 59, 59, 999999999, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := EndOfWeek(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestBeginOfMonth(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBeginOfMonth")
+
+	expected := time.Date(2022, 2, 1, 0, 0, 0, 0, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := BeginOfMonth(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestEndOfMonth(t *testing.T) {
+	assert := internal.NewAssert(t, "TestEndOfMonth")
+
+	expected := time.Date(2022, 2, 28, 23, 59, 59, 999999999, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := EndOfMonth(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestBeginOfYear(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBeginOfYear")
+
+	expected := time.Date(2022, 1, 1, 0, 0, 0, 0, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := BeginOfYear(td)
+
+	assert.Equal(expected, actual)
+}
+
+func TestEndOfYear(t *testing.T) {
+	assert := internal.NewAssert(t, "TestEndOfYear")
+
+	expected := time.Date(2022, 12, 31, 23, 59, 59, 999999999, time.Local)
+	td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+	actual := EndOfYear(td)
+
+	assert.Equal(expected, actual)
+}
--- a/docs/datetime.md
+++ b/docs/datetime.md
@@ -22,6 +22,19 @@ import (
 - [AddDay](#AddDay)
 - [AddHour](#AddHour)
 - [AddMinute](#AddMinute)
+- [BeginOfMinute](#BeginOfMinute)
+- [BeginOfHour](#BeginOfHour)
+- [BeginOfDay](#BeginOfDay)
+- [BeginOfWeek](#BeginOfWeek)
+- [BeginOfMonth](#BeginOfMonth)
+- [BeginOfYear](#BeginOfYear)
+
+- [EndOfMinute](#EndOfMinute)
+- [EndOfHour](#EndOfHour)
+- [EndOfDay](#EndOfDay)
+- [EndOfWeek](#EndOfWeek)
+- [EndOfMonth](#EndOfMonth)
+- [EndOfYear](#EndOfYear)
 - [GetNowDate](#GetNowDate)
 - [GetNowTime](#GetNowTime)
 - [GetNowDateTime](#GetNowDateTime)
@@ -142,6 +155,331 @@ func main() {
 }
 ```

+### <span id="BeginOfMinute">BeginOfMinute</span>
+<p>Return beginning minute time of day.</p>
+
+<b>Signature:</b>
+
+```go
+func BeginOfMinute(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfMinute(td)
+    fmt.Println(bm) //2022-02-15 15:48:00 +0800 CST
+}
+```
+
+### <span id="BeginOfHour">BeginOfHour</span>
+<p>Return zero time of day.</p>
+
+<b>Signature:</b>
+
+```go
+func BeginOfHour(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfHour(td)
+    fmt.Println(bm) //2022-02-15 15:00:00 +0800 CST
+}
+```
+
+### <span id="BeginOfDay">BeginOfDay</span>
+<p>Return begin time of day.</p>
+
+<b>Signature:</b>
+
+```go
+func BeginOfDay(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfDay(td)
+    fmt.Println(bm) //2022-02-15 00:00:00 +0800 CST
+}
+```
+
+
+
+### <span id="BeginOfWeek">BeginOfWeek</span>
+<p>Return beginning time of week, week begin from Sunday.</p>
+
+<b>Signature:</b>
+
+```go
+func BeginOfWeek(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfWeek(td)
+    fmt.Println(bm) //2022-02-13 00:00:00 +0800 CST
+}
+```
+
+
+
+### <span id="BeginOfMonth">BeginOfMonth</span>
+<p>Return beginning time of month</p>
+
+<b>Signature:</b>
+
+```go
+func BeginOfMonth(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfMonth(td)
+    fmt.Println(bm) //2022-02-01 00:00:00 +0800 CST
+}
+```
+
+
+### <span id="BeginOfYear">BeginOfYear</span>
+<p>Return beginning time of year.</p>
+
+<b>Signature:</b>
+
+```go
+func BeginOfYear(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfYear(td)
+    fmt.Println(bm) //2022-01-01 00:00:00 +0800 CST
+}
+```
+
+
+
+### <span id="EndOfMinute">EndOfMinute</span>
+<p>Return end time minute of day.</p>
+
+<b>Signature:</b>
+
+```go
+func EndOfMinute(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfMinute(td)
+    fmt.Println(bm) //2022-02-15 15:48:59.999999999 +0800 CST
+}
+```
+
+### <span id="EndOfHour">EndOfHour</span>
+<p>Return end time hour of day.</p>
+
+<b>Signature:</b>
+
+```go
+func EndOfHour(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfHour(td)
+    fmt.Println(bm) //2022-02-15 15:59:59.999999999 +0800 CST
+}
+```
+
+### <span id="EndOfDay">EndOfDay</span>
+<p>Return end time hour of day.</p>
+
+<b>Signature:</b>
+
+```go
+func EndOfDay(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfDay(td)
+    fmt.Println(bm) //2022-02-15 23:59:59.999999999 +0800 CST
+}
+```
+
+
+
+### <span id="EndOfWeek">EndOfWeek</span>
+<p>Return end time of week, week end with Saturday.</p>
+
+<b>Signature:</b>
+
+```go
+func EndOfWeek(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfWeek(td)
+    fmt.Println(bm) //2022-02-19 23:59:59.999999999 +0800 CST
+}
+```
+
+
+
+### <span id="EndOfMonth">EndOfMonth</span>
+<p>Return end time of month</p>
+
+<b>Signature:</b>
+
+```go
+func EndOfMonth(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfMonth(td)
+    fmt.Println(bm) //2022-02-28 23:59:59.999999999 +0800 CST
+}
+```
+
+
+### <span id="EndOfYear">EndOfYear</span>
+<p>Return beginning time of year.</p>
+
+<b>Signature:</b>
+
+```go
+func EndOfYear(t time.Time) time.Time
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfYear(td)
+    fmt.Println(bm) //2022-12-31 23:59:59.999999999 +0800 CST
+}
+```
+
+
 ### <span id="GetNowDate">GetNowDate</span>
 <p>Get current date string, format is yyyy-mm-dd.</p>

--- a/docs/datetime_zh-CN.md
+++ b/docs/datetime_zh-CN.md
@@ -22,12 +22,24 @@ import (
 - [AddDay](#AddDay)
 - [AddHour](#AddHour)
 - [AddMinute](#AddMinute)
+- [BeginOfMinute](#BeginOfMinute)
+- [BeginOfHour](#BeginOfHour)
+- [BeginOfDay](#BeginOfDay)
+- [BeginOfWeek](#BeginOfWeek)
+- [BeginOfMonth](#BeginOfMonth)
+- [BeginOfYear](#BeginOfYear)
+
+- [EndOfMinute](#EndOfMinute)
+- [EndOfHour](#EndOfHour)
+- [EndOfDay](#EndOfDay)
+- [EndOfWeek](#EndOfWeek)
+- [EndOfMonth](#EndOfMonth)
+- [EndOfYear](#EndOfYear)
 - [GetNowDate](#GetNowDate)
 - [GetNowTime](#GetNowTime)
 - [GetNowDateTime](#GetNowDateTime)
 - [GetZeroHourTimestamp](#GetZeroHourTimestamp)
 - [GetNightTimestamp](#GetNightTimestamp)
-
 - [FormatTimeToStr](#FormatTimeToStr)
 - [FormatStrToTime](#FormatStrToTime)

@@ -142,6 +154,331 @@ func main() {
 }
 ```

+### <span id="BeginOfMinute">BeginOfMinute</span>
+<p>返回指定时间的分钟开始时间</p>
+
+<b>函数签名:</b>
+
+```go
+func BeginOfMinute(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfMinute(td)
+    fmt.Println(bm) //2022-02-15 15:48:00 +0800 CST
+}
+```
+
+### <span id="BeginOfHour">BeginOfHour</span>
+<p>返回指定时间的小时开始时间</p>
+
+<b>函数签名:</b>
+
+```go
+func BeginOfHour(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfHour(td)
+    fmt.Println(bm) //2022-02-15 15:00:00 +0800 CST
+}
+```
+
+### <span id="BeginOfDay">BeginOfDay</span>
+<p>返回指定时间的当天开始时间</p>
+
+<b>函数签名:</b>
+
+```go
+func BeginOfDay(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfDay(td)
+    fmt.Println(bm) //2022-02-15 00:00:00 +0800 CST
+}
+```
+
+
+
+### <span id="BeginOfWeek">BeginOfWeek</span>
+<p>返回指定时间的星期开始时间</p>
+
+<b>函数签名:</b>
+
+```go
+func BeginOfWeek(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfWeek(td)
+    fmt.Println(bm) //2022-02-13 00:00:00 +0800 CST
+}
+```
+
+
+
+### <span id="BeginOfMonth">BeginOfMonth</span>
+<p>返回指定时间的当月开始时间</p>
+
+<b>函数签名:</b>
+
+```go
+func BeginOfMonth(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfMonth(td)
+    fmt.Println(bm) //2022-02-01 00:00:00 +0800 CST
+}
+```
+
+
+### <span id="BeginOfYear">BeginOfYear</span>
+<p>返回指定时间的当年开始时间</p>
+
+<b>函数签名:</b>
+
+```go
+func BeginOfYear(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.BeginOfYear(td)
+    fmt.Println(bm) //2022-01-01 00:00:00 +0800 CST
+}
+```
+
+
+
+### <span id="EndOfMinute">EndOfMinute</span>
+<p>返回指定时间的分钟结束时间</p>
+
+<b>函数签名:</b>
+
+```go
+func EndOfMinute(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfMinute(td)
+    fmt.Println(bm) //2022-02-15 15:48:59.999999999 +0800 CST
+}
+```
+
+### <span id="EndOfHour">EndOfHour</span>
+<p>返回指定时间的小时结束时间</p>
+
+<b>函数签名:</b>
+
+```go
+func EndOfHour(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfHour(td)
+    fmt.Println(bm) //2022-02-15 15:59:59.999999999 +0800 CST
+}
+```
+
+### <span id="EndOfDay">EndOfDay</span>
+<p>返回指定时间的当天结束时间.</p>
+
+<b>函数签名:</b>
+
+```go
+func EndOfDay(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfDay(td)
+    fmt.Println(bm) //2022-02-15 23:59:59.999999999 +0800 CST
+}
+```
+
+
+
+### <span id="EndOfWeek">EndOfWeek</span>
+<p>返回指定时间的星期结束时间</p>
+
+<b>函数签名:</b>
+
+```go
+func EndOfWeek(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfWeek(td)
+    fmt.Println(bm) //2022-02-19 23:59:59.999999999 +0800 CST
+}
+```
+
+
+
+### <span id="EndOfMonth">EndOfMonth</span>
+<p>返回指定时间的月份结束时间</p>
+
+<b>函数签名:</b>
+
+```go
+func EndOfMonth(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfMonth(td)
+    fmt.Println(bm) //2022-02-28 23:59:59.999999999 +0800 CST
+}
+```
+
+
+### <span id="EndOfYear">EndOfYear</span>
+<p>返回指定时间的年份结束时间</p>
+
+<b>函数签名:</b>
+
+```go
+func EndOfYear(t time.Time) time.Time
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "time"
+    "github.com/duke-git/lancet/datetime"
+)
+
+func main() {
+    td := time.Date(2022, 2, 15, 15, 48, 40, 112, time.Local)
+    bm := datetime.EndOfYear(td)
+    fmt.Println(bm) //2022-12-31 23:59:59.999999999 +0800 CST
+}
+```
+
+
 ### <span id="GetNowDate">GetNowDate</span>
 <p>获取当天日期，返回格式：yyyy-mm-dd</p>

--- a/docs/function.md
+++ b/docs/function.md
@@ -26,7 +26,6 @@ import (
 - [Compose](#Compose)
 - [Debounced](#Debounced)
 - [Delay](#Delay)
- [Delay](#Delay)
 - [Watcher](#Watcher)

 <div STYLE="page-break-after: always;"></div>
--- a/docs/function_zh-CN.md
+++ b/docs/function_zh-CN.md
@@ -26,7 +26,6 @@ import (
 - [Compose](#Compose)
 - [Debounced](#Debounced)
 - [Delay](#Delay)
- [Delay](#Delay)
 - [Watcher](#Watcher)

 <div STYLE="page-break-after: always;"></div>
--- a/docs/mathutil.md
+++ b/docs/mathutil.md
@@ -0,0 +1,233 @@
+# Mathutil
+Package mathutil implements some functions for math calculation.
+
+<div STYLE="page-break-after: always;"></div>
+
+## Source:
+
+[https://github.com/duke-git/lancet/blob/main/mathutil/mathutil.go](https://github.com/duke-git/lancet/blob/main/mathutil/mathutil.go)
+
+
+<div STYLE="page-break-after: always;"></div>
+
+## Example:
+```go
+import (
+    "github.com/duke-git/lancet/mathutil"
+)
+```
+
+<div STYLE="page-break-after: always;"></div>
+
+## Index
+- [Exponent](#Exponent)
+- [Fibonacci](#Fibonacci)
+- [Factorial](#Factorial)
+- [Percent](#Percent)
+- [RoundToFloat](#RoundToFloat)
+- [RoundToString](#RoundToString)
+- [TruncRound](#TruncRound)
+
+<div STYLE="page-break-after: always;"></div>
+
+## Documentation
+
+
+### <span id="Exponent">Exponent</span>
+<p>Calculate x to the nth power.</p>
+
+<b>Signature:</b>
+
+```go
+func Exponent(x, n int64) int64
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Exponent(10, 0)) //1
+	fmt.Println(mathutil.Exponent(10, 1)) //10
+	fmt.Println(mathutil.Exponent(10, 2)) //100
+}
+```
+
+
+
+### <span id="Fibonacci">Fibonacci</span>
+<p>Calculate the nth number of fibonacci sequence.</p>
+
+<b>Signature:</b>
+
+```go
+func Fibonacci(first, second, n int) int
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Fibonacci(1, 1, 1)) //1
+	fmt.Println(mathutil.Fibonacci(1, 1, 2)) //1
+	fmt.Println(mathutil.Fibonacci(1, 1, 3)) //2
+	fmt.Println(mathutil.Fibonacci(1, 1, 4)) //3
+	fmt.Println(mathutil.Fibonacci(1, 1, 5)) //5
+}
+```
+
+
+
+### <span id="Factorial">Factorial</span>
+<p>Calculate the factorial of x.</p>
+
+<b>Signature:</b>
+
+```go
+func Factorial(x uint) uint
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Factorial(0)) //1
+	fmt.Println(mathutil.Factorial(1)) //1
+	fmt.Println(mathutil.Factorial(2)) //2
+	fmt.Println(mathutil.Factorial(3)) //6
+}
+```
+
+
+
+### <span id="Percent">Percent</span>
+<p>calculate the percentage of val to total, retain n decimal places.</p>
+
+<b>Signature:</b>
+
+```go
+func Percent(val, total float64, n int) float64
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Percent(1, 2, 2)) //1
+	fmt.Println(mathutil.Percent(0.1, 0.3, 2)) //33.33
+}
+```
+
+
+
+### <span id="RoundToFloat">RoundToFloat</span>
+<p>Round float up to n decimal places.</p>
+
+<b>Signature:</b>
+
+```go
+func RoundToFloat(x float64, n int) float64
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.RoundToFloat(0, 0)) //0
+	fmt.Println(mathutil.RoundToFloat(0, 1)) //0
+	fmt.Println(mathutil.RoundToFloat(0.124, 2)) //0.12
+	fmt.Println(mathutil.RoundToFloat(0.125, 2)) //0.13
+	fmt.Println(mathutil.RoundToFloat(0.125, 3)) //0.125
+}
+```
+
+
+
+
+### <span id="RoundToString">RoundToString</span>
+<p>Round float up to n decimal places. will return string.</p>
+
+<b>Signature:</b>
+
+```go
+func RoundToString(x float64, n int) string
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.RoundToString(0, 0)) //"0"
+	fmt.Println(mathutil.RoundToString(0, 1)) //"0.0:
+	fmt.Println(mathutil.RoundToString(0.124, 2)) //"0.12"
+	fmt.Println(mathutil.RoundToString(0.125, 2)) //"0.13"
+	fmt.Println(mathutil.RoundToString(0.125, 3)) //"0.125"
+}
+```
+
+
+
+### <span id="TruncRound">TruncRound</span>
+<p>Round float off n decimal places.</p>
+
+<b>Signature:</b>
+
+```go
+func TruncRound(x float64, n int) float64
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.TruncRound(0, 0)) //0
+	fmt.Println(mathutil.TruncRound(0, 1)) //0
+	fmt.Println(mathutil.TruncRound(0.124, 2)) //0.12
+	fmt.Println(mathutil.TruncRound(0.125, 2)) //0.12
+	fmt.Println(mathutil.TruncRound(0.125, 3)) //0.125
+}
+```
+
+
+
--- a/docs/mathutil_zh-CN.md
+++ b/docs/mathutil_zh-CN.md
@@ -0,0 +1,234 @@
+# Mathutil
+mathutil包实现了一些数学计算的函数.
+
+<div STYLE="page-break-after: always;"></div>
+
+## 源码:
+
+[https://github.com/duke-git/lancet/blob/main/mathutil/mathutil.go](https://github.com/duke-git/lancet/blob/main/mathutil/mathutil.go)
+
+
+<div STYLE="page-break-after: always;"></div>
+
+## 用法:
+```go
+import (
+    "github.com/duke-git/lancet/mathutil"
+)
+```
+
+<div STYLE="page-break-after: always;"></div>
+
+## 目录
+- [Exponent](#Exponent)
+- [Fibonacci](#Fibonacci)
+- [Factorial](#Factorial)
+
+- [Percent](#Percent)
+- [RoundToFloat](#RoundToFloat)
+- [RoundToString](#RoundToString)
+- [TruncRound](#TruncRound)
+
+<div STYLE="page-break-after: always;"></div>
+
+## Documentation
+
+
+### <span id="Exponent">Exponent</span>
+<p>指数计算（x的n次方）</p>
+
+<b>函数签名:</b>
+
+```go
+func Exponent(x, n int64) int64
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Exponent(10, 0)) //1
+	fmt.Println(mathutil.Exponent(10, 1)) //10
+	fmt.Println(mathutil.Exponent(10, 2)) //100
+}
+```
+
+
+
+### <span id="Fibonacci">Fibonacci</span>
+<p>计算斐波那契数列的第n个数</p>
+
+<b>函数签名:</b>
+
+```go
+func Fibonacci(first, second, n int) int
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Fibonacci(1, 1, 1)) //1
+	fmt.Println(mathutil.Fibonacci(1, 1, 2)) //1
+	fmt.Println(mathutil.Fibonacci(1, 1, 3)) //2
+	fmt.Println(mathutil.Fibonacci(1, 1, 4)) //3
+	fmt.Println(mathutil.Fibonacci(1, 1, 5)) //5
+}
+```
+
+
+
+### <span id="Factorial">Factorial</span>
+<p>计算阶乘</p>
+
+<b>函数签名:</b>
+
+```go
+func Factorial(x uint) uint
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Factorial(0)) //1
+	fmt.Println(mathutil.Factorial(1)) //1
+	fmt.Println(mathutil.Factorial(2)) //2
+	fmt.Println(mathutil.Factorial(3)) //6
+}
+```
+
+
+
+### <span id="Percent">Percent</span>
+<p>计算百分比，保留n位小数</p>
+
+<b>函数签名:</b>
+
+```go
+func Percent(val, total float64, n int) float64
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.Percent(1, 2, 2)) //1
+	fmt.Println(mathutil.Percent(0.1, 0.3, 2)) //33.33
+}
+```
+
+
+
+### <span id="RoundToFloat">RoundToFloat</span>
+<p>四舍五入，保留n位小数</p>
+
+<b>函数签名:</b>
+
+```go
+func RoundToFloat(x float64, n int) float64
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.RoundToFloat(0, 0)) //0
+	fmt.Println(mathutil.RoundToFloat(0, 1)) //0
+	fmt.Println(mathutil.RoundToFloat(0.124, 2)) //0.12
+	fmt.Println(mathutil.RoundToFloat(0.125, 2)) //0.13
+	fmt.Println(mathutil.RoundToFloat(0.125, 3)) //0.125
+}
+```
+
+
+
+
+### <span id="RoundToString">RoundToString</span>
+<p>四舍五入，保留n位小数，返回字符串</p>
+
+<b>函数签名:</b>
+
+```go
+func RoundToString(x float64, n int) string
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.RoundToString(0, 0)) //"0"
+	fmt.Println(mathutil.RoundToString(0, 1)) //"0.0:
+	fmt.Println(mathutil.RoundToString(0.124, 2)) //"0.12"
+	fmt.Println(mathutil.RoundToString(0.125, 2)) //"0.13"
+	fmt.Println(mathutil.RoundToString(0.125, 3)) //"0.125"
+}
+```
+
+
+
+### <span id="TruncRound">TruncRound</span>
+<p>截短n位小数（不进行四舍五入）</p>
+
+<b>函数签名:</b>
+
+```go
+func TruncRound(x float64, n int) float64
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/mathutil"
+)
+
+func main() {
+	fmt.Println(mathutil.TruncRound(0, 0)) //0
+	fmt.Println(mathutil.TruncRound(0, 1)) //0
+	fmt.Println(mathutil.TruncRound(0.124, 2)) //0.12
+	fmt.Println(mathutil.TruncRound(0.125, 2)) //0.12
+	fmt.Println(mathutil.TruncRound(0.125, 3)) //0.125
+}
+```
+
+
+
--- a/docs/netutil.md
+++ b/docs/netutil.md
@@ -7,7 +7,7 @@ Package netutil contains functions to get net information and send http request.

 [https://github.com/duke-git/lancet/blob/main/netutil/net.go](https://github.com/duke-git/lancet/blob/main/netutil/net.go)

-[https://github.com/duke-git/lancet/blob/main/netutil/request.go](https://github.com/duke-git/lancet/blob/main/netutil/request.go)
+[https://github.com/duke-git/lancet/blob/main/netutil/http.go](https://github.com/duke-git/lancet/blob/main/netutil/http.go)

 <div STYLE="page-break-after: always;"></div>

@@ -23,6 +23,8 @@ import (
 ## Index
 - [ConvertMapToQueryString](#ConvertMapToQueryString)
 - [GetInternalIp](#GetInternalIp)
+- [GetIps](#GetIps)
+- [GetMacAddrs](#GetMacAddrs)
 - [GetPublicIpInfo](#GetPublicIpInfo)
 - [IsPublicIP](#IsPublicIP)
 - [HttpGet](#HttpGet)
@@ -99,6 +101,60 @@ func main() {



+### <span id="GetIps">GetIps</span>
+<p>Get all ipv4 list.</p>
+
+<b>Signature:</b>
+
+```go
+func GetIps() []string
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+	"net"
+    "github.com/duke-git/lancet/netutil"
+)
+
+func main() {
+	ips := netutil.GetIps()
+	fmt.Println(ips) //[192.168.1.9]
+}
+```
+
+
+
+### <span id="GetMacAddrs">GetMacAddrs</span>
+<p>Get all mac addresses list.</p>
+
+<b>Signature:</b>
+
+```go
+func GetMacAddrs() []string {
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+	"net"
+    "github.com/duke-git/lancet/netutil"
+)
+
+func main() {
+	addrs := netutil.GetMacAddrs()
+	fmt.Println(addrs)
+}
+```
+
+
+
 ### <span id="GetPublicIpInfo">GetPublicIpInfo</span>
 <p>Get public ip information.</p>

--- a/docs/netutil_zh-CN.md
+++ b/docs/netutil_zh-CN.md
@@ -7,7 +7,7 @@ netutil网络包支持获取ip地址，发送http请求。

 [https://github.com/duke-git/lancet/blob/main/netutil/net.go](https://github.com/duke-git/lancet/blob/main/netutil/net.go)

-[https://github.com/duke-git/lancet/blob/main/netutil/request.go](https://github.com/duke-git/lancet/blob/main/netutil/request.go)
+[https://github.com/duke-git/lancet/blob/main/netutil/http.go](https://github.com/duke-git/lancet/blob/main/netutil/http.go)

 <div STYLE="page-break-after: always;"></div>

@@ -23,6 +23,8 @@ import (
 ## 目录
 - [ConvertMapToQueryString](#ConvertMapToQueryString)
 - [GetInternalIp](#GetInternalIp)
+- [GetIps](#GetIps)
+- [GetMacAddrs](#GetMacAddrs)
 - [GetPublicIpInfo](#GetPublicIpInfo)
 - [IsPublicIP](#IsPublicIP)
 - [HttpGet](#HttpGet)
@@ -98,6 +100,59 @@ func main() {
 ```


+### <span id="GetIps">GetIps</span>
+<p>获取ipv4地址列表</p>
+
+<b>函数签名:</b>
+
+```go
+func GetIps() []string
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+	"net"
+    "github.com/duke-git/lancet/netutil"
+)
+
+func main() {
+	ips := netutil.GetIps()
+	fmt.Println(ips) //[192.168.1.9]
+}
+```
+
+
+
+### <span id="GetMacAddrs">GetMacAddrs</span>
+<p>获取mac地址列</p>
+
+<b>函数签名:</b>
+
+```go
+func GetMacAddrs() []string {
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+	"net"
+    "github.com/duke-git/lancet/netutil"
+)
+
+func main() {
+	addrs := netutil.GetMacAddrs()
+	fmt.Println(addrs)
+}
+```
+
+

 ### <span id="GetPublicIpInfo">GetPublicIpInfo</span>
 <p>获取公网ip信息</p>
--- a/docs/random.md
+++ b/docs/random.md
@@ -23,6 +23,7 @@ import (
 - [RandBytes](#RandBytes)
 - [RandInt](#RandInt)
 - [RandString](#RandString)
+- [UUIdV4](#UUIdV4)

 <div STYLE="page-break-after: always;"></div>

@@ -105,3 +106,33 @@ func main() {
 ```


+
+
+### <span id="UUIdV4">UUIdV4</span>
+<p>Generate a random UUID of version 4 according to RFC 4122.</p>
+
+<b>Signature:</b>
+
+```go
+func UUIdV4() (string, error)
+```
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/random"
+)
+
+func main() {
+	uuid, err := random.UUIdV4()
+    if err != nil {
+        return
+    }
+	fmt.Println(uuid)
+}
+```
+
+
--- a/docs/random_zh-CN.md
+++ b/docs/random_zh-CN.md
@@ -23,6 +23,8 @@ import (
 - [RandBytes](#RandBytes)
 - [RandInt](#RandInt)
 - [RandString](#RandString)
+- [UUIdV4](#UUIdV4)
+

 <div STYLE="page-break-after: always;"></div>

@@ -105,3 +107,32 @@ func main() {
 ```


+
+### <span id="UUIdV4">UUIdV4</span>
+<p>生成UUID v4字符串</p>
+
+<b>函数签名:</b>
+
+```go
+func UUIdV4() (string, error)
+```
+<b>例子:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/random"
+)
+
+func main() {
+	uuid, err := random.UUIdV4()
+    if err != nil {
+        return
+    }
+	fmt.Println(uuid)
+}
+```
+
+
--- a/formatter/formatter_internal.go
+++ b/formatter/formatter_internal.go
--- a/function/function.go
+++ b/function/function.go
@@ -13,6 +13,7 @@ import (
 func After(n int, fn interface{}) func(args ...interface{}) []reflect.Value {
 	// Catch programming error while constructing the closure
 	mustBeFunction(fn)
+
 	return func(args ...interface{}) []reflect.Value {
 		n--
 		if n < 1 {
@@ -66,12 +67,18 @@ func Compose(fnList ...func(...interface{}) interface{}) func(...interface{}) in

 // Delay make the function execution after delayed time
 func Delay(delay time.Duration, fn interface{}, args ...interface{}) {
+	// Catch programming error while constructing the closure
+	mustBeFunction(fn)
+
 	time.Sleep(delay)
 	invokeFunc(fn, args...)
 }

 // Debounced creates a debounced function that delays invoking fn until after wait duration have elapsed since the last time the debounced function was invoked.
 func Debounced(fn func(), duration time.Duration) func() {
+	// Catch programming error while constructing the closure
+	mustBeFunction(fn)
+
 	timer := time.NewTimer(duration)
 	timer.Stop()

@@ -91,6 +98,7 @@ func Debounced(fn func(), duration time.Duration) func() {
 func Schedule(d time.Duration, fn interface{}, args ...interface{}) chan bool {
 	// Catch programming error while constructing the closure
 	mustBeFunction(fn)
+
 	quit := make(chan bool)
 	go func() {
 		for {
--- a/function/function_internal.go
+++ b/function/function_internal.go
--- a/logo.png
+++ b/logo.png
--- a/mathutil/mathutil.go
+++ b/mathutil/mathutil.go
@@ -0,0 +1,92 @@
+// Copyright 2021 dudaodong@gmail.com. All rights reserved.
+// Use of this source code is governed by MIT license
+
+// Package mathutil implements some functions for math calculation.
+package mathutil
+
+import (
+	"fmt"
+	"math"
+	"strconv"
+	"strings"
+)
+
+// Exponent calculate x^n
+func Exponent(x, n int64) int64 {
+	if n == 0 {
+		return 1
+	}
+
+	t := Exponent(x, n/2)
+
+	if n%2 == 1 {
+		return t * t * x
+	}
+
+	return t * t
+}
+
+// Fibonacci calculate fibonacci number before n
+func Fibonacci(first, second, n int) int {
+	if n <= 0 {
+		return 0
+	}
+	if n < 3 {
+		return 1
+	} else if n == 3 {
+		return first + second
+	} else {
+		return Fibonacci(second, first+second, n-1)
+	}
+}
+
+// Factorial calculate x!
+func Factorial(x uint) uint {
+	var f uint = 1
+	for ; x > 1; x-- {
+		f *= x
+	}
+	return f
+}
+
+// Percent calculate the percentage of val to total
+func Percent(val, total float64, n int) float64 {
+	if total == 0 {
+		return float64(0)
+	}
+	tmp := val / total * 100
+	res := RoundToFloat(tmp, n)
+
+	return res
+}
+
+// RoundToString round up to n decimal places
+func RoundToString(x float64, n int) string {
+	tmp := math.Pow(10.0, float64(n))
+	x *= tmp
+	x = math.Round(x)
+	res := strconv.FormatFloat(x/tmp, 'f', n, 64)
+	return res
+}
+
+// RoundToFloat round up to n decimal places
+func RoundToFloat(x float64, n int) float64 {
+	tmp := math.Pow(10.0, float64(n))
+	x *= tmp
+	x = math.Round(x)
+	return x / tmp
+}
+
+// TruncRound round off n decimal places
+func TruncRound(x float64, n int) float64 {
+	floatStr := fmt.Sprintf("%."+strconv.Itoa(n+1)+"f", x)
+	temp := strings.Split(floatStr, ".")
+	var newFloat string
+	if len(temp) < 2 || n >= len(temp[1]) {
+		newFloat = floatStr
+	} else {
+		newFloat = temp[0] + "." + temp[1][:n]
+	}
+	res, _ := strconv.ParseFloat(newFloat, 64)
+	return res
+}
--- a/mathutil/mathutil_test.go
+++ b/mathutil/mathutil_test.go
@@ -0,0 +1,72 @@
+package mathutil
+
+import (
+	"testing"
+
+	"github.com/duke-git/lancet/internal"
+)
+
+func TestExponent(t *testing.T) {
+	assert := internal.NewAssert(t, "TestExponent")
+
+	assert.Equal(int64(1), Exponent(10, 0))
+	assert.Equal(int64(10), Exponent(10, 1))
+	assert.Equal(int64(100), Exponent(10, 2))
+}
+
+func TestFibonacci(t *testing.T) {
+	assert := internal.NewAssert(t, "TestFibonacci")
+
+	assert.Equal(0, Fibonacci(1, 1, 0))
+	assert.Equal(1, Fibonacci(1, 1, 1))
+	assert.Equal(1, Fibonacci(1, 1, 2))
+	assert.Equal(5, Fibonacci(1, 1, 5))
+}
+
+func TestFactorial(t *testing.T) {
+	assert := internal.NewAssert(t, "TestFactorial")
+
+	assert.Equal(uint(1), Factorial(0))
+	assert.Equal(uint(1), Factorial(1))
+	assert.Equal(uint(2), Factorial(2))
+	assert.Equal(uint(6), Factorial(3))
+}
+
+func TestPercent(t *testing.T) {
+	assert := internal.NewAssert(t, "TestPercent")
+
+	assert.Equal(float64(50), Percent(1, 2, 2))
+	assert.Equal(float64(33.33), Percent(0.1, 0.3, 2))
+}
+
+func TestRoundToFloat(t *testing.T) {
+	assert := internal.NewAssert(t, "TestRoundToFloat")
+
+	assert.Equal(RoundToFloat(0, 0), float64(0))
+	assert.Equal(RoundToFloat(0, 1), float64(0))
+	assert.Equal(RoundToFloat(0.124, 2), float64(0.12))
+	assert.Equal(RoundToFloat(0.125, 2), float64(0.13))
+	assert.Equal(RoundToFloat(0.125, 3), float64(0.125))
+	assert.Equal(RoundToFloat(33.33333, 2), float64(33.33))
+}
+
+func TestRoundToString(t *testing.T) {
+	assert := internal.NewAssert(t, "TestRoundToString")
+
+	assert.Equal(RoundToString(0, 0), "0")
+	assert.Equal(RoundToString(0, 1), "0.0")
+	assert.Equal(RoundToString(0.124, 2), "0.12")
+	assert.Equal(RoundToString(0.125, 2), "0.13")
+	assert.Equal(RoundToString(0.125, 3), "0.125")
+}
+
+func TestTruncRound(t *testing.T) {
+	assert := internal.NewAssert(t, "TestTruncRound")
+
+	assert.Equal(TruncRound(0, 0), float64(0))
+	assert.Equal(TruncRound(0, 1), float64(0))
+	assert.Equal(TruncRound(0.124, 2), float64(0.12))
+	assert.Equal(TruncRound(0.125, 2), float64(0.12))
+	assert.Equal(TruncRound(0.125, 3), float64(0.125))
+	assert.Equal(TruncRound(33.33333, 2), float64(33.33))
+}
--- a/netutil/request.go
+++ b/netutil/request.go
--- a/netutil/request_test.go
+++ b/netutil/request_test.go
--- a/netutil/net.go
+++ b/netutil/net.go
@@ -47,6 +47,46 @@ func GetPublicIpInfo() (*PublicIpInfo, error) {
 	return &ip, nil
 }

+// GetIps return all ipv4 of system
+func GetIps() []string {
+	var ips []string
+
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return ips
+	}
+
+	for _, addr := range addrs {
+		ipNet, isValid := addr.(*net.IPNet)
+		if isValid && !ipNet.IP.IsLoopback() {
+			if ipNet.IP.To4() != nil {
+				ips = append(ips, ipNet.IP.String())
+			}
+		}
+	}
+	return ips
+}
+
+// GetMacAddrs get mac address
+func GetMacAddrs() []string {
+	var macAddrs []string
+
+	nets, err := net.Interfaces()
+	if err != nil {
+		return macAddrs
+	}
+
+	for _, net := range nets {
+		macAddr := net.HardwareAddr.String()
+		if len(macAddr) == 0 {
+			continue
+		}
+		macAddrs = append(macAddrs, macAddr)
+	}
+
+	return macAddrs
+}
+
 // PublicIpInfo public ip info: country, region, isp, city, lat, lon, ip
 type PublicIpInfo struct {
 	Status      string  `json:"status"`
--- a/netutil/net_internal.go
+++ b/netutil/net_internal.go
@@ -157,16 +157,13 @@ func setQueryParam(req *http.Request, reqUrl string, queryParam interface{}) err

 func setBodyByte(req *http.Request, body interface{}) error {
 	if body != nil {
-		var bodyByte []byte
-		if body != nil {
-			switch v := body.(type) {
-			case []byte:
-				bodyByte = v
-			default:
-				return errors.New("body type should be []byte")
-			}
+		switch b := body.(type) {
+		case []byte:
+			req.Body = ioutil.NopCloser(bytes.NewReader(b))
+			req.ContentLength = int64(len(b))
+		default:
+			return errors.New("body type should be []byte")
 		}
-		req.Body = ioutil.NopCloser(bytes.NewReader(bodyByte))
 	}
 	return nil
 }
--- a/netutil/net_test.go
+++ b/netutil/net_test.go
@@ -42,3 +42,13 @@ func TestIsPublicIP(t *testing.T) {
 		assert.Equal(expected[i], actual)
 	}
 }
+
+func TestGetIps(t *testing.T) {
+	ips := GetIps()
+	t.Log(ips)
+}
+
+func TestGetMacAddrs(t *testing.T) {
+	macAddrs := GetMacAddrs()
+	t.Log(macAddrs)
+}
--- a/random/random.go
+++ b/random/random.go
@@ -6,6 +6,7 @@ package random

 import (
 	crand "crypto/rand"
+	"fmt"
 	"io"
 	"math/rand"
 	"time"
@@ -48,3 +49,18 @@ func RandBytes(length int) []byte {
 	}
 	return b
 }
+
+// UUIdV4 generate a random UUID of version 4 according to RFC 4122
+func UUIdV4() (string, error) {
+	uuid := make([]byte, 16)
+
+	n, err := io.ReadFull(crand.Reader, uuid)
+	if n != len(uuid) || err != nil {
+		return "", err
+	}
+
+	uuid[8] = uuid[8]&^0xc0 | 0x80
+	uuid[6] = uuid[6]&^0xf0 | 0x40
+
+	return fmt.Sprintf("%x-%x-%x-%x-%x", uuid[0:4], uuid[4:6], uuid[6:8], uuid[8:10], uuid[10:]), nil
+}
--- a/random/random_test.go
+++ b/random/random_test.go
@@ -47,3 +47,16 @@ func TestRandBytes(t *testing.T) {

 	assert.Equal([]byte{}, RandBytes(0))
 }
+
+func TestUUIdV4(t *testing.T) {
+	assert := internal.NewAssert(t, "TestUUIdV4")
+
+	uuid, err := UUIdV4()
+	if err != nil {
+		t.Log(err)
+		t.Fail()
+	}
+
+	isUUiDV4 := regexp.MustCompile(`^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$`)
+	assert.Equal(true, isUUiDV4.MatchString(uuid))
+}
--- a/slice/slice_internal.go
+++ b/slice/slice_internal.go
--- a/strutil/string_internal.go
+++ b/strutil/string_internal.go
Author	SHA1	Message	Date
dudaodong	7ac6816532	docs: add Factorial	2022-03-04 17:37:49 +08:00
dudaodong	81c4216699	release v1.2.6	2022-03-04 17:31:38 +08:00
dudaodong	2e30389703	test: add TestTruncRound	2022-03-04 17:30:47 +08:00
dudaodong	0e1d5cf04b	docs: add doc for mathutil package	2022-03-04 17:28:53 +08:00
dudaodong	4e2d84e4fc	feat: add mathutil package	2022-03-03 15:55:36 +08:00
dudaodong	13ee045b99	docs: add section 'How to Contribute'	2022-03-01 14:55:42 +08:00
dudaodong	f1fd4c876b	fmt: gofmt function.go	2022-02-28 10:11:07 +08:00
dudaodong	cd63b2b18f	docs: add func UUIdV4 in readme file	2022-02-28 10:09:23 +08:00
dudaodong	bab9b4a6b3	release v1.2.5	2022-02-25 16:39:03 +08:00
dudaodong	b3c34578bf	fix: set request body content-length	2022-02-25 16:38:32 +08:00
dudaodong	f26477904e	refactor: set body byte for http post request	2022-02-25 15:31:39 +08:00
dudaodong	85886cf618	docs: add func UUIdV4	2022-02-20 11:09:51 +08:00
dudaodong	a19a861552	feat: add func UUIdV4	2022-02-20 10:16:15 +08:00
dudaodong	96d57a6d24	docs: remove duplicated	2022-02-19 21:53:27 +08:00
dudaodong	b48155c249	refactor: rename files _util.go to _internal.go	2022-02-19 21:52:10 +08:00
dudaodong	41685022c0	refactor: rename files _util.go to _internal.go	2022-02-19 21:51:58 +08:00
dudaodong	4e7274ce05	fix: check fn param must be function	2022-02-17 19:51:52 +08:00
dudaodong	2384b0e51f	docs: fix func link mistake	2022-02-16 14:26:03 +08:00
dudaodong	6b6b938d1e	docs: fix func link mistake	2022-02-16 14:24:18 +08:00
dudaodong	29d8987909	docs: update readme file	2022-02-16 14:12:42 +08:00
dudaodong	43fb3f1a06	release v1.2.4	2022-02-16 14:10:25 +08:00
dudaodong	34c28fece3	docs&refactor: rename request.go to http.go	2022-02-15 17:46:07 +08:00
dudaodong	40c2402493	feat: add func GetIps and GetMacAddrs	2022-02-15 17:38:09 +08:00
dudaodong	c965e79bfc	docs: add doc for begin and end time funcs	2022-02-15 16:37:48 +08:00
dudaodong	eeadb1fecb	feat: add funcs for get begin and end time for year, month, week, day, hour, minute	2022-02-15 16:07:59 +08:00
dudaodong	1dd826f050	add logo png and update readme file	2022-02-08 14:43:57 +08:00