How to find the array index with a value?

javascript arrays indexof
joedborg picture joedborg · Sep 8, 2011 · Viewed 427.1k times · Source

Say I've got this

imageList = [100,200,300,400,500];

Which gives me

[0]100 [1]200 etc.

Is there any way in JavaScript to return the index with the value?

I.e. I want the index for 200, I get returned 1.

Answer

voigtan picture voigtan · Sep 8, 2011

You can use indexOf:

var imageList = [100,200,300,400,500];
var index = imageList.indexOf(200); // 1

You will get -1 if it cannot find a value in the array.

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