js实现前端下载文件

//下载文件

    _download:function (filename,content){

    var blob = new Blob([content], {type: 'text'});

        var a =document.getElementById('downloadFtsetBtn');

        if(a==undefined){

            a=document.createElement('a');

            a.id='downloadFtsetBtn';

            a.style.display='none';

            a.target='_blank';

            document.body.appendChild(a);

        }

        try{

            var URL=window.URL || window.webkitURL;

            a.href=URL.createObjectURL(blob);

            a.download = filename;

            if (typeof navigator.msSaveBlob == "function"){  //IE

                navigator.msSaveBlob(blob,filename);
　　　　　　　　　　 }
         a.click();

        catch(e){

       }

 }