php message Warning: Missing boundary in multipart/form-data POST data in Unknown on line 0

Question

This is my javascript

function ajax_post(){
            // Create our XMLHttpRequest object
            var hr = new XMLHttpRequest();
            // Create          


        

Answer 1

This works as well. Taken from https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Type

const config = { headers: { Authorization: Bearer ${localStorage.token}, "Content-Type": "multipart/form-data; boundary=---------------------------974767299852498929531610575" } };

Answer 2

The browser sets the correct headers (including the correct multipart boundary indication in the Content-type) if you haven't manually specified anything.

So all you need to do is remove the following line:

 hr.setRequestHeader("Content-type", "multipart/form-data");

Otherwise you will need to set the boundary yourself as it is suggested by Ellias Van Ootegem in Uploading a file with XMLHttprequest - Missing boundary in multipart/form-data:

hr.setRequestHeader("Content-type","multipart/form-data; charset=utf-8; boundary=" + Math.random().toString().substr(2));