问题：前端文本框输入字符串，提交后端后接收为null。
报错：
Character decoding failed. Parameter [modifyToPwd] with value [%QAZuyt2017] has been ignored. Note that the name and value quoted here may be corrupted due to the failed decoding. Use debug level logging to see the original, non-corrupted values.
原因：
%
解决：
前端 ，escape(string)