Regular expression to remove a file's extension

javascript regex filenames
Andreas Grech picture Andreas Grech · Nov 30, 2009 · Viewed 70.4k times · Source

I am in need of a regular expression that can remove the extension of a filename, returning only the name of the file.

Here are some examples of inputs and outputs:

myfile.png     -> myfile
myfile.png.jpg -> myfile.png

I can obviously do this manually (ie removing everything from the last dot) but I'm sure that there is a regular expression that can do this by itself.

Just for the record, I am doing this in JavaScript

Answer

Boldewyn picture Boldewyn · Nov 30, 2009

Just for completeness: How could this be achieved without Regular Expressions?

var input = 'myfile.png';
var output = input.substr(0, input.lastIndexOf('.')) || input;

The || input takes care of the case, where lastIndexOf() provides a -1. You see, it's still a one-liner.

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