<form action="/upload.html" method="post" target="iframe_1" enctype="multipart/form-data">

        <iframe style="display: none"  id="iframe_1" name="iframe_1" src="" onload="loadIframe();"></iframe>

        <input type="text" name="user" />

        <input type="file" name="fafafa" />

        <input type="submit" />

    </form>

  <script>

    function loadIframe() {

            console.log(1);

            // 获取iframe内部的内容

            var str_json = $('#iframe_1').contents().find('body').text();

            var obj = JSON.parse(str_json);

            if (obj.status){

                var img = document.createElement('img');

                img.src = "/" + obj.path;

                $('#imgs').append(img);

            }

        }

    </script>