lancet/docs/random.md

# Random

Package random implements some basic functions to generate random int and string.

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

## Source:

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

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

## Usage:

```go
import (
    "github.com/duke-git/lancet/v2/random"
)
```

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

## Index

-   [RandBytes](#RandBytes)
-   [RandInt](#RandInt)
-   [RandString](#RandString)
-   [RandUpper](#RandUpper)
-   [RandLower](#RandLower)
-   [RandNumeral](#RandNumeral)
-   [RandNumeralOrLetter](#RandNumeralOrLetter)
-   [UUIdV4](#UUIdV4)

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

## Documentation

### <span id="RandBytes">RandBytes</span>

<p>Generate random byte slice.</p>

<b>Signature:</b>

```go
func RandBytes(length int) []byte
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    randBytes := random.RandBytes(4)
    fmt.Println(randBytes)
}
```

### <span id="RandInt">RandInt</span>

<p>Generate random int between min and max, may contain min, not max.</p>

<b>Signature:</b>

```go
func RandInt(min, max int) int
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    rInt := random.RandInt(1, 10)
    fmt.Println(rInt)
}
```

### <span id="RandString">RandString</span>

<p>Generate random given length string. only contains letter (a-zA-Z)</p>

<b>Signature:</b>

```go
func RandString(length int) string
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    randStr := random.RandString(6)
    fmt.Println(randStr) //pGWsze
}
```

### <span id="RandUpper">RandUpper</span>

<p>Generate a random upper case string</p>

<b>Signature:</b>

```go
func RandUpper(length int) string
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    randStr := random.RandString(6)
    fmt.Println(randStr) //PACWGF
}
```

### <span id="RandLower">RandLower</span>

<p>Generate a random lower case string</p>

<b>Signature:</b>

```go
func RandLower(length int) string
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    randStr := random.RandLower(6)
    fmt.Println(randStr) //siqbew
}
```

### <span id="RandNumeral">RandNumeral</span>

<p>Generate a random numeral string</p>

<b>Signature:</b>

```go
func RandNumeral(length int) string
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    randStr := random.RandNumeral(6)
    fmt.Println(randStr) //035172
}
```

### <span id="RandNumeralOrLetter">RandNumeralOrLetter</span>

<p>generate a random numeral or letter string</p>

<b>Signature:</b>

```go
func RandNumeralOrLetter(length int) string
```

<b>Example:</b>

```go
package main

import (
    "fmt"
    "github.com/duke-git/lancet/v2/random"
)

func main() {
    randStr := random.RandNumeralOrLetter(6)
    fmt.Println(randStr) //0aW7cQ
}
```

### <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/v2/random"
)

func main() {
    uuid, err := random.UUIdV4()
    if err != nil {
        return
    }
    fmt.Println(uuid)
}
```