- LimitMixedStringLen

platformapi/weixinapi/cgibin.go

@@ -2,6 +2,10 @@ package weixinapi
 
 import "git.rosy.net.cn/baseapi/utils"
 
+const (
+	MaxRemarkByteCount = 30
+)
+
 func (a *API) CBSetToken(newToken string) bool {
 	curToken := a.CBGetToken()
 	if curToken != newToken {
@@ -49,10 +53,11 @@ func (a *API) CBMessageTemplateSend(userOpenID, templateID, downloadURL string,
 	return err
 }
 
+// remark的字节数不超过30个字节
 func (a *API) CBUpdateRemark(userOpenID, remark string) (err error) {
 	bodyJson := map[string]interface{}{
 		"openid": userOpenID,
-		"remark": remark,
+		"remark": utils.LimitMixedStringLen(remark, MaxRemarkByteCount),
 	}
 	_, err = a.AccessAPI("cgi-bin/user/info/updateremark", nil, string(utils.MustMarshal(bodyJson)))
 	return err

platformapi/weixinapi/cgibin_test.go

@@ -31,7 +31,9 @@ func TestCBMessageTemplateSend(t *testing.T) {
 }
 
 func TestCBUpdateRemark(t *testing.T) {
-	err := api.CBUpdateRemark("oYN_ust9hXKEvEv0X6Mq6nlAWs_E", "徐大仙")
+	remark := "一二三四五六七八九十"
+	t.Log(len(remark))
+	err := api.CBUpdateRemark("oYN_ust9hXKEvEv0X6Mq6nlAWs_E", remark)
 	if err != nil {
 		t.Log(err)
 	}

utils/utils.go

@@ -238,23 +238,65 @@ func Base64DecodeMultiString(strs ...string) (decodedData [][]byte, err error) {
 	return decodedData, nil
 }
 
-func LimitStringLen(str string, maxLen int) (limitedStr string) {
-	if maxLen > 0 {
-		if strLen := len(str); strLen > maxLen {
-			str = str[:maxLen]
+// 只适合与纯英文的情况
+func LimitStringLen(str string, maxByteCount int) (limitedStr string) {
+	if maxByteCount > 0 {
+		if strLen := len(str); strLen > maxByteCount {
+			str = str[:maxByteCount]
 		}
 	}
 	return str
 }
 
-func LimitUTF8StringLen(str string, maxLen int) (limitedStr string) {
-	if maxLen > 0 {
-		if len(str) > maxLen {
+// 限制的是字符数，不是字节数
+func LimitUTF8StringLen(str string, maxRuneCount int) (limitedStr string) {
+	if maxRuneCount > 0 {
+		if len(str) > maxRuneCount {
 			runeList := []rune(str)
-			if len(runeList) > maxLen {
-				str = string(runeList[:maxLen])
+			if len(runeList) > maxRuneCount {
+				str = string(runeList[:maxRuneCount])
 			}
 		}
 	}
 	return str
 }
+
+// 限制的是字节数，正常处理乱码
+func LimitMixedStringLen(str string, maxByteCount int) (limitedStr string) {
+	if maxByteCount <= 0 {
+		return str
+	}
+	length := len(str)
+	if maxByteCount >= length {
+		return str
+	}
+	bs := []byte(str)[:maxByteCount]
+	bl := 0
+	for i := len(bs) - 1; i >= 0; i-- {
+		switch {
+		case bs[i] >= 0 && bs[i] <= 127:
+			return string(bs[:i+1])
+		case bs[i] >= 128 && bs[i] <= 191:
+			bl++
+		case bs[i] >= 192 && bs[i] <= 253:
+			cl := 0
+			switch {
+			case bs[i]&252 == 252:
+				cl = 6
+			case bs[i]&248 == 248:
+				cl = 5
+			case bs[i]&240 == 240:
+				cl = 4
+			case bs[i]&224 == 224:
+				cl = 3
+			default:
+				cl = 2
+			}
+			if bl+1 == cl {
+				return string(bs[:i+cl])
+			}
+			return string(bs[:i])
+		}
+	}
+	return ""
+}

utils/utils_test.go

@@ -214,4 +214,24 @@ func TestLimitUTF8StringLen(t *testing.T) {
 			t.Fatalf("%v处理错误，预期:%v，实际:%s", v[0], v[2], str)
 		}
 	}
+	for _, v := range [][]interface{}{
+		[]interface{}{
+			"大家好abc",
+			10,
+			"大家好a",
+		},
+		[]interface{}{
+			"a大家好123",
+			8,
+			"a大家",
+		},
+	} {
+		str := LimitMixedStringLen(v[0].(string), v[1].(int))
+		if str != v[2] {
+			t.Fatalf("%v处理错误，预期:%v，实际:%s", v[0], v[2], str)
+		}
+	}
+	t.Log(LimitStringLen("a大家好1234567", 8))
+	t.Log(LimitUTF8StringLen("a大家好1234567", 8))
+	t.Log(LimitMixedStringLen("a大家好1234567", 8))
 }