php – 如何在ajax文件上传中显示进度条

我的代码发布了ajax请求,但它没有显示进度条.请帮助更正代码以显示工作进度条.

$(document).ready(function () {
    $("#uploadbutton").click(function () {
    var filename = $("#file_path$i").val(); //get form data;

    $.ajax({
      type: "html",url: "share.PHP",//onwhich post ajax data;
      enctype: 'multipart/form-data',data: {
        file: filename
      },success: function () {
        alert("Data Uploaded: ");
      }
    });
 });
});

解决方法

@whitneyit：我们可以使用xhr：ajax函数跟踪文件上传这样的东西

$.ajax({
                url: 'handler/FileUploader.ashx?FileName=' + file.name,//server script to process data
                type: 'POST',xhr: function () {
                    myXhr = $.ajaxSettings.xhr();
                    if (myXhr.upload) {
                        myXhr.upload.addEventListener('progress',progressHandlingFunction,false);
                    }
                    return myXhr;
                },success: function (result) {                    
                    //On success if you want to perform some tasks.
                },data: file,cache: false,contentType: false,processData: false
            });
            function progressHandlingFunction(e) {
                if (e.lengthComputable) {
                    var s = parseInt((e.loaded / e.total) * 100);
                    $("#progress" + currFile).text(s + "%");
                    $("#progbarWidth" + currFile).width(s + "%");
                    if (s == 100) {
                        triggerNextFileUpload();
                    }
                }
            }