Coding with Jesse

Using Hash for JavaScript Debugging

September 26th, 2007

No, I don't recommend smoking hash before doing your JavaScript debugging :) But I did figure out a technique which you can use to switch a page in and out of debugging mode.

What happens if you need to debug a site that's getting traffic, and you don't want everyone getting your alert() messages or whatever else you need to debug?

Well why not check location.hash and look for a special keyword:

function debug_mode() {
    return location.hash == '#debug';
}

if (debug_mode()) {
    alert('We are in debug mode!');
}

Now you can just add #debug to the URL (and hit enter) to turn on debug mode, or just drop the #debug to turn it off. You can even have more than one special "mode" and use different hash values to switch between these modes.

About the author

Jesse Skinner Hi, I'm Jesse Skinner. I work with development teams to speed up and stabilize web applications, reduce server costs, fix difficult bugs, modernize legacy applications, and improve developer productivity. I'd love to hear from you and see how I can make your life easier.