防止多次调用getImageUrl

@@ -66,6 +66,11 @@ class Images
      */
     public static function getImageUrl($fileName, $width, $height, $mode = 2, $bucket = 'goodsimg')
     {
+        if (substr($fileName, 0, 2) === '//') {
+            //防止多次调用getImageUrl
+            $fileName = 'http:' . $fileName;
+        }
+
         if (!is_string($fileName)) {
             return self::template(self::$default_image, $bucket, $mode);
         }