如何从php服务器上传和读取json响应的html表单post文件

i am trying file uploading to php my server.file and data uploading through multi part /form-data ,the file and data received on php server but in my php server return json response .please help me how to read json response in my webpage and if its success(code=0) means it redirect another page .the php sever is common for both android and web pages .json response look like {"code":0,"message":"success"} i am trying file uploading to php my server.fil