HTTP HEAD Request in Javascript/Ajax?

Is it possible to do a HTTP Head request solely using an XMLHTTPRequest in JavaScript?

My motivation is to conserve bandwidth.

If not, is it possible to fake it?


Easy, just use the HEAD method, instead of GET or POST:

function UrlExists(url, callback)
    var http = new XMLHttpRequest();'HEAD', url);
    http.onreadystatechange = function() {
        if (this.readyState == this.DONE) {
            callback(this.status != 404);

This is just a short example to show how to use the HEAD method. Production code may need more fine-grained callbacks for different result states (success, failure, timeout), and may use different event handlers (onload, onerror and ontimeout rather than onreadystatechange).

Need Your Help

Need help 301 htaccess RedirectMatch

apache .htaccess mod-rewrite

i need to do a trick directly after the file extension

Factory Initializer + Singleton

c# singleton factory

I wrote a non-static Generic class instantiator for my Abstract Factory design, and use Singleton approach to make sure that only 1 instance of the instantiator will be initialized for every client

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