var xhr = null;
if(window.ActiveXObject){ //如果是IE瀏覽器
xhr = new ActiveXObject("Microsoft.XMLHTTP");
}else if(window.XMLHttpRequest){ //非IE瀏覽器
xhr = new XMLHttpRequest();
}
//上傳過程中綁定uploadProgress(complete,total,index,evt)方法,即時更新進度條,要傳遞參數只能通過bind來綁定,且第一個參數爲null,evt爲當前時間,evt.loaded * 100 / evt.total 已完成的百分比
xhr.upload.addEventListener("progress", uploadProgress.bind(null,complete,total,index), false);
xhr.addEventListener("load", uploadComplete.bind(null,uploadId,dataFile,filename,complete,total,index), false);
xhr.addEventListener("error", uploadFailed, false);
xhr.addEventListener("abort", uploadCanceled, false);
var cancelBtn = $('.upload_item').eq(index).find(".upload_btn");
cancelBtn.on("click",cancelUpload.bind(null,xhr,cancelBtn));
xhr.open('PUT', "http://***.oss-cn-beijing.aliyuncs.com/.......";//put爲這次請求的類型
xhr.setRequestHeader("Content-Type", dataFile.type);
xhr.send(data);//data表示要上傳的文件