客户端获取上传文件大小

function GetfileSize(addFileuploadCmp) {    var agent = window.navigator.userAgent;    var fileSize = 0;    if (agent.indexOf("Chrome") >= 1) {            fileSize = addFileuploadCmp.fileInputEl.dom.files[0].fileSize;        }       else if (agent.indexOf("Firefox") >= 1) {            fileSize = addFileuploadCmp.fileInputEl.dom.files[0].fileSize;        } else if (1==1) { //紧紧只是ie            var fso = new ActiveXObject("Scripting.FileSystemObject");            fileSize = fso.GetFile(addFileuploadCmp.getValue()).size;        }        return fileSize;};