FileUpload问题

这个问题是在使用ajax提交文件时没有格式化编辑

var form = new FormData(document.getElementById("form_info_mass"));

//使用formData才可以将文件上传时解析
      $.ajax({
             url: "/send/all",
             data: form,
             type: "post",
             contentType:"multipart/form-data",
             cache: false,
             processData: false,
             contentType: false,
             success: function (data) {
                 console.log("list 对象   "+ JSON.stringify(data) );
             },
             error: function (XMLHttpRequest, textStatus, errorThrown) {
               }, 
             beforeSend: function () {
               },
             complete: function () {
               }
         });