How to execute javascript code directly in your browser
This trick is not known by everyone though it is really simple.
The address bar
In the address bar, you simply write
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javascript:/*some javascript code here*/;void(0);
As easy as that.
In fact, it’s the same thing as creating a link that executes some javascript code.
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<a href="javascript:alert(‘Some code from a link’);">Execute code from javascript</a>
The only thing I add is the void(0); at the end of the code to avoid a “bug” that reloads the page.
Hey, if you want to write a bookmarklet, you’ll probably use this technique.
Firebug
These days, you can’t write javascript without using Firebug (apart if you are a javascript magician). You just can’t. For the ones who don’t know Firebug, I’ll describe it in 7 words : javascript debugger, html inspector, css modifier, fun.
On the “Console” tag, there’s one line beginning with “>>>” at the bottom. This is the javascript executer. If you click the red arrow at the end of the line, you have a multi-line executer.
I always use it to write and test the javascript snippets on this site.
What can I do with that?
Everything you want. In fact, I use it for these purpose :
- write code snippet for Javascript Kata
- write a bookmarklet
- debug javascript on Firefox
- have fun on other’s sites