Get the response Content-Type header from XHR

Question

I would like to see whether the header was text/html or text/xml. If it was text/html then there was an error and I would rather catch that before proceeding.

Solution

Use the getResponseHeader() method.

Minimal example:

<script>
function hand () {
        console.log(this.getResponseHeader('content-type'));
}
var x = new XMLHttpRequest();
x.onreadystatechange = hand;
x.open('GET', 'index.html', true);
x.send();
</script>

Comments

[700 Software]

Why did you call it hand?

[Quentin]

Because I was too lazy to type out handler in full.

[Ωmega]

Would that work even with Transfer-Encoding: chunked when some headers are sent after the message body?

[Dai]

@Ωmega I think it depends on the XHR's readyState (LOADING as opposed to DONE).

[GChuf]

Thanks, this will come in handy