🐛 fix determine gbk

utils/code.go

@@ -0,0 +1,59 @@
+package utils
+
+import (
+	"bytes"
+	"golang.org/x/text/encoding/simplifiedchinese"
+	"golang.org/x/text/transform"
+	"io/ioutil"
+	"unicode/utf8"
+)
+
+func IsGBK(data []byte) bool {
+	length := len(data)
+	var i = 0
+	for i < length {
+		if data[i] <= 0x7f {
+			//编码0~127,只有一个字节的编码，兼容ASCII码
+			i++
+			continue
+		} else {
+			//大于127的使用双字节编码，落在gbk编码范围内的字符
+			if data[i] >= 0x81 &&
+				data[i] <= 0xfe &&
+				data[i+1] >= 0x40 &&
+				data[i+1] <= 0xfe &&
+				data[i+1] != 0xf7 {
+				i += 2
+				continue
+			} else {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+const (
+	GBK     string = "GBK"
+	UTF8    string = "UTF8"
+	UNKNOWN string = "UNKNOWN"
+)
+
+func GetStrCoding(data []byte) string {
+	if utf8.Valid(data) {
+		return UTF8
+	} else if IsGBK(data) {
+		return GBK
+	} else {
+		return UNKNOWN
+	}
+}
+
+func GbkToUtf8(s []byte) ([]byte, error) {
+	reader := transform.NewReader(bytes.NewReader(s), simplifiedchinese.GBK.NewDecoder())
+	d, e := ioutil.ReadAll(reader)
+	if e != nil {
+		return nil, e
+	}
+	return d, nil
+}