FormData异步上传

1.代码片段一：

 ajaxUpload: function () {
      var url = this.$avatarForm.attr('action'),
          data = new FormData(this.$avatarForm[0]),
          _this = this;

      $.ajax(url, {
        type: 'post',
        data: data,
        dataType: 'json',
        processData: false,
        contentType: false,

        beforeSend: function () {
          _this.submitStart();
        },

        success: function (data) {
          _this.submitDone(data);
        },

        error: function (XMLHttpRequest, textStatus, errorThrown) {
          _this.submitFail(textStatus || errorThrown);
        },

        complete: function () {
          _this.submitEnd();
        }
      });
    },

2.代码片段二：

$(document).ready(function (e) {
    $("#uploadForm").on('submit',(function(e) {
        e.preventDefault();
        $.ajax({
            url: "upload.php",
            type: "POST",
            data:  new FormData(this),
            contentType: false,
            cache: false,
            processData:false,
            success: function(data)
            {
            $("#targetLayer").html(data);
            },
            error: function()
            {
            }
       });
    }));
});