$.ajax({
                url: url,
                type: "POST",
                data: form,
                processData:false,    //必须
                contentType:false,    //必须
                xhr: function() {        //ajax进度条，直接拿过去就可以用
                    var xhr = $.ajaxSettings.xhr();
                    if (xhr.upload) {
                        xhr.upload.addEventListener("progress", function (e) {
                            var loaded = e.loaded; //已经上传大小情况
                            var tot = e.total; //附件总大小
                            var per = Math.floor(100 * loaded / tot); //已经上传的百分比
                            console.log(per)
                            $('.progress-bar').css('width',per+'%');   //这里指的是进度条的宽度等于完成的百分比
                            // $.fn.progressInit.draw(per + '%'); //绘制经度条
                        }, false);
                        return xhr;
                    }
                },
                success: function () {

                },
                error: function () {
                    
                }
            })