Run arbitrary snippets of JS code in your browser with one keystroke:
- Launch 'Live Preview' to open your page in Chrome
- Select some JS code
- Press Ctrl+Shift+J
The code is evaluated as if you'd just typed it into the Developer Tools console. This is often not the same result as if you save the code and refresh your web page. For example:
- Doesn't update the body of existing functions. E.g. running Eval in Browser on an edited method body will not change what happens next time the method is called; it's the same as copy-pasting the method body into the console. However, you can overwrite an entire function in the global namespace, and you can eval extra code to explicitly remove & replace event listeners that were using the original copy of the function.
- Doesn't change the result of code that's already been run. E.g. changing a global variable that's read by a constructor doesn't
affect any existing instances of that object. However, re-executing a protype assignment (e.g.
MyClass.prototype.foo = 42;) works well. - Aways runs in global scope, so vars next to the selected code aren't accessible (unless the selection is also in the global scope). Variables and functions inside a module or otherwise nested inside a wrapper function aren't accessible unless they've been exported to the global scope.
But when used judiciously, this is a great way to quickly debug or tweak the state of your page without doing a full refresh and losing the page's current state.
Eval in Browser is an extension for Brackets, a new open-source code editor for the web.
To install extensions:
- Choose File > Extension Manager and select the Available tab
- Search for this extension
- Click Install!
MIT-licensed -- see main.js for details.
Brackets Sprint 33 or newer.