如何利用jquery做出文件上传加载

//进度条 
 
0%
 
 
 //要拖动到的地方 

var dz = $('#main_content_center'); dz.ondragover = function(ev) { //阻止浏览器默认打开文件的操作 ev.preventDefault(); } dz.ondrop = function(ev) { ev.preventDefault(); var files = ev.dataTransfer.files; var len = files.length,i = 0; while (i < len) { var filesName=files[i].name; var extStart=filesName.lastIndexOf("."); var ext=filesName.substring(extStart,filesName.length).toUpperCase(); if(ext!=".JPG"&&ext!=".PNG"&&ext!=".XML"){ //判断是否是需要的问件类型 TS.errorAlert("请选择.jpg、.png、.xml类型的文件上传！"); return false; }else{ test(files[i]); } i++; } $(".parent-dlg").show(); } function test(a){ var formData = new FormData(); formData.append("name", a.name); formData.append("size", a.size); formData.append("data", a); $.ajax({ url:'', type:'post', data:formData, cache: false, processData: false, contentType: false, xhr: function(){ var xhr = $.ajaxSettings.xhr(); if(onprogress && xhr.upload) { xhr.upload.addEventListener("progress" , onprogress, false); return xhr; } } }) }; function onprogress(evt){ var loaded = evt.loaded; //已经上传大小情况 var tot = evt.total; //附件总大小 var per = Math.floor(100*loaded/tot); //已经上传的百分比 $(".progress-label").html( per +"%" ); $(".son").css("width" , per +"%"); if(per>=100){ $(".parent-dlg").hide(); } }

.parent-dlg{position: absolute;width:400px; height:20px; border:1px solid #aaaaaa;border-radius:3px;top:30%;left:50%;z-index:9999;margin-left:-200px;display:none;} .parent-dlg .progress-label{position: absolute;left: 50%;top: 4px;font-weight: bold;text-shadow: 1px 1px 0 #fff;} .parent-dlg .son {width:0; height:100%; background-color:#cccccc; text-align:center; line-height:20px; font-size:16px; font-weight:bold;}