Why my string replace is not working in JavaScript?

Question

I'm trying to replace a placeholder in a string I'm generating.

My string looks like this:

 var s = 'module("SlapOS UI Basic Interaction"); ' +
         'asyncTest( "${base_url}", function() { ' +
         ' expect( __number__ ); ' +
         ' ok(testForElement("div#global-panel"), "element present");' +
         ' start(); })';

And I want to replace __number__.

I can get the index correctly like so:

 s.indexOf("__number__");

but replacing does not work...

 s.replace("__number__", "1");

Question:
What am I doing wrong here? Makes no sense to my why it does not work.

Works for me. Hate to ask this, but maybe you're forgetting to assign the result of the replace to something? — David Sherret, Mar 28 '14 at 16:48

score 2 · Accepted Answer · edited Sep 09 '17 at 18:30

2

The replace method does not modify the existing string. It returns a new one.

var result = s.replace("__number__", "1");

edited Sep 09 '17 at 18:30

Bryan

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answered Mar 28 '14 at 16:49

Denys Lieu

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darn.... I think I always forget :-) – frequent Mar 28 '14 at 16:50

Why my string replace is not working in JavaScript?

1 Answers1