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32 lines
996 B
Markdown
32 lines
996 B
Markdown
# Interpolate A String Into A Regex
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You can build up strings with concatenation or the template literal syntax. If
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you're incorporating variables as part of this string building, that's called
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interpolation.
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But what if you need to interpolate variables into a regular expression
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(regex)?
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A regex literal looks like this:
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```javascript
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const myRegex = /^Some Customizable Text$/;
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```
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This works great for fixed strings, but won't cut it if you need to work
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_variable_ strings.
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What's needed to work with variables is the
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[`RegExp`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp)
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constructor:
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```javascript
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const customizableString = "Some Customizable Text";
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const myRegex = new RegExp(`^${customizableString}$`);
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```
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You can build up some string with string variables and regex syntax and `new
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RegExp()` will turn it into a regex.
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[source](https://makandracards.com/makandra/15879-javascript-how-to-generate-a-regular-expression-from-a-string)
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