doc: add doc for IsGBK'

docs/validator.md

@@ -47,6 +47,7 @@ import (
 - [IsUrl](#IsUrl)
 - [IsWeakPassword](#IsWeakPassword)
 - [IsZeroValue](#IsZeroValue)
+- [IsGBK](#IsGBK)
   
 
 <div STYLE="page-break-after: always;"></div>
@@ -821,7 +822,34 @@ func main() {
 ```
 
 
-
+### <span id="IsGBK">IsGBK</span>
+<p>Checks if data encoding is gbk(Chinese character internal code extension specification). this function is implemented by whether double bytes fall within the encoding range of gbk,while each byte of utf-8 encoding format falls within the encoding range of gbk.Therefore, utf8.valid() should be called first to check whether it is not utf-8 encoding and then call IsGBK() to check gbk encoding. like the example.</p>
+
+<b>Signature:</b>
+
+```go
+func IsGBK(data []byte) bool
+```
+<b>Example:</b>
+
+```go
+import (
+	"fmt"
+	"github.com/duke-git/lancet/v2/validator"
+)
+
+func main() {
+	data := []byte("你好")
+	
+	// check utf8 first
+	if utf8.Valid(data) {
+		fmt.Println("data encoding is utf-8")
+	}else if(validator.IsGBK(data)) {
+		fmt.Println("data encoding is GBK")
+	}
+	fmt.Println("data encoding is unknown")
+}
+```
 
 
 

docs/validator_zh-CN.md

@@ -47,6 +47,7 @@ import (
 - [IsUrl](#IsUrl)
 - [IsWeakPassword](#IsWeakPassword)
 - [IsZeroValue](#IsZeroValue)
+- [IsGBK](#IsGBK)
   
 
 <div STYLE="page-break-after: always;"></div>
@@ -820,3 +821,31 @@ func main() {
 }
 ```
 
+### <span id="IsGBK">IsGBK</span>
+<p>检查数据编码是否为gbk（汉字内部代码扩展规范）。该函数的实现取决于双字节是否在gbk的编码范围内，而utf-8编码格式的每个字节都在gbk编码范围内。因此，应该首先调用utf8.valid检查它是否是utf-8编码，然后调用IsGBK检查gbk编码。如示例所示。</p>
+
+<b>函数签名:</b>
+
+```go
+func IsGBK(data []byte) bool
+```
+<b>例子:</b>
+
+```go
+import (
+	"fmt"
+	"github.com/duke-git/lancet/v2/validator"
+)
+
+func main() {
+	data := []byte("你好")
+	
+	// 先检查utf8编码
+	if utf8.Valid(data) {
+		fmt.Println("data encoding is utf-8")
+	}else if(validator.IsGBK(data)) {
+		fmt.Println("data encoding is GBK")
+	}
+	fmt.Println("data encoding is unknown")
+}
+```

validator/validator.go

@@ -275,7 +275,7 @@ func IsZeroValue(value any) bool {
 	return reflect.DeepEqual(rv.Interface(), reflect.Zero(rv.Type()).Interface())
 }
 
-// IsGBK check if data encoinge is gbk
+// IsGBK check if data encoding is gbk
 // Note: this function is implemented by whether double bytes fall within the encoding range of gbk,
 // while each byte of utf-8 encoding format falls within the encoding range of gbk.
 // Therefore, utf8.valid() should be called first to check whether it is not utf-8 encoding,