javascript - Downloading file from ajax result using blob -

i use code download excel file server.

$.ajax({     headers: client.authorize(),     url: '/server/url',     type: 'post',     contenttype: "application/json; charset=utf-8",     data: json.stringify(jsondata),     success: function (data) {         alert('data size: ' + data.length);         var blob = new blob([data], { type: "application/vnd.ms-excel" });         alert('blob size: ' + data.length);         var url = window.url || window.webkiturl;         var downloadurl = url.createobjecturl(blob);         document.location = downloadurl;     }, }); 

the problem experience though data , blob sizes identical, moment document.location gets assigned i'm prompted download almoste 2 times larger excel file. , when try open it, excel complains wrong file format , opened file contains lot of garbage, though required text still there.

any ideas causing , how avoid it?

so solved problem using ajax 2. natively supports binary streams. can't use jquery that, unless base64 encode everything, apparently.

working code looks this:

var xhr = new xmlhttprequest(); xhr.open('post', '/le/url', true); xhr.responsetype = 'blob'; $.each(server.authorization(), function(k, v) {     xhr.setrequestheader(k, v); }); xhr.setrequestheader('content-type', 'application/json; charset=utf-8'); xhr.onload = function(e) {     preloader.modal('hide');     if (this.status == 200) {         var blob = new blob([this.response], {type: 'application/vnd.ms-excel'});         var downloadurl = url.createobjecturl(blob);         var = document.createelement("a");         a.href = downloadurl;         a.download = "data.xls";         document.body.appendchild(a);         a.click();     } else {         alert('unable download excel.')     } }; xhr.send(json.stringify(jsondata)); 

hope helps.