图片上传修改

@@ -59,7 +59,7 @@ class MemberController extends CommentController
     public function upload_wx_pic(){
         $access_token = $this->getAccessToken();
         $img_str = $this->request->param('media','','string');
-        $a['g'] = json_decode($img_str);
+        $a['g'] = json_encode($img_str);
         $img_arr = explode(',',rtrim($img_str,','));
         $foldername = 'petavatar/'.date('Ymd');
         $imgurls = '';