freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../regular-expressions/use-capture-groups-to-searc...

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---
id: 587d7dbb367417b2b2512bab
title: Use Capture Groups to Search and Replace
challengeType: 1
---
## Description
<section id='description'>
Searching is useful. However, you can make searching even more powerful when it also changes (or replaces) the text you match.
You can search and replace text in a string using <code>.replace()</code> on a string. The inputs for <code>.replace()</code> is first the regex pattern you want to search for. The second parameter is the string to replace the match or a function to do something.
<blockquote>let wrongText = "The sky is silver.";<br>let silverRegex = /silver/;<br>wrongText.replace(silverRegex, "blue");<br>// Returns "The sky is blue."</blockquote>
You can also access capture groups in the replacement string with dollar signs (<code>$</code>).
<blockquote>"Code Camp".replace(/(\w+)\s(\w+)/, '$2 $1');<br>// Returns "Camp Code"</blockquote>
</section>
## Instructions
<section id='instructions'>
Write a regex so that it will search for the string <code>"good"</code>. Then update the <code>replaceText</code> variable to replace <code>"good"</code> with <code>"okey-dokey"</code>.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: You should use <code>.replace()</code> to search and replace.
testString: assert(code.match(/\.replace\(.*\)/), 'You should use <code>.replace()</code> to search and replace.');
- text: Your regex should change <code>"This sandwich is good."</code> to <code>"This sandwich is okey-dokey."</code>
testString: assert(result == "This sandwich is okey-dokey." && replaceText === "okey-dokey", 'Your regex should change <code>"This sandwich is good."</code> to <code>"This sandwich is okey-dokey."</code>');
- text: You should not change the last line.
testString: assert(code.match(/result\s*=\s*huhText\.replace\(.*?\)/), 'You should not change the last line.');
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
let huhText = "This sandwich is good.";
let fixRegex = /change/; // Change this line
let replaceText = ""; // Change this line
let result = huhText.replace(fixRegex, replaceText);
```
</div>
</section>
## Solution
<section id='solution'>
```js
// solution required
```
</section>