update check base64

utils/util.go

@@ -101,23 +101,19 @@ func readPrivateKey() (*ecdsa.PrivateKey, error) {
 // IsBase64ImageStr 检查字符串是否是 Base64 编码的图像数据
 func IsBase64ImageStr(imageStr string) (bool, []byte, string, string) {
 	// 移除可能的前缀（如 "data:image/png;base64,"）
-	imageStrArr := strings.SplitN(imageStr, ",", 2)
-	base64CodePrefix := ""
-	base64Code := ""
-	if len(imageStrArr) == 1 {
-		base64Code = imageStrArr[0]
-		base64CodePrefix = "data:image/png;base64"
-	} else {
-		base64CodePrefix = imageStrArr[0]
-		base64Code = imageStrArr[1]
+	imageStrArr := strings.Split(imageStr, ",")
+	if len(imageStrArr) < 2 {
+		return false, nil, "", ""
 	}
+	base64CodePrefix := imageStrArr[0]
+	base64Code := imageStrArr[1]
 	decodeBytes, err := base64.StdEncoding.DecodeString(base64Code)
 	if err != nil {
 		log.WithError(err).Error("base64 decode string failed")
 		return false, nil, "", ""
 	}
 	dataSuffix := strings.Split(base64CodePrefix, ";")
-	if len(dataSuffix) < 1 {
+	if len(dataSuffix) < 2 {
 		return false, nil, "", ""
 	}
 	formatStrArr := strings.Split(dataSuffix[0], ":")