JavaScript: Escape a string to use in a regular expression

JavaScript fundamental (ES6 Syntax): Exercise-239 with Solution

Escape String for Regex

Write a JavaScript program to escape a string to use in a regular expression.

• Use String.prototype.replace() to escape special characters.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
// Define a function 'escapeRegExp' to escape special characters in a regular expression pattern
const escapeRegExp = str => 
  // Replace special characters in the input string 'str' with their escaped versions
  str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');

// Test the 'escapeRegExp' function with a string containing special characters
console.log(escapeRegExp('(test)')); // Output: \(test\)

Output:

\(test\)

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-239-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that escapes all special characters in a string so it can be safely used in a regular expression.
• Write a JavaScript function that converts a string to a regex-safe string by prefixing special characters with a backslash.
• Write a JavaScript program that iterates over a string and escapes characters like . * + ? ^ $ { } ( ) | [ ] \.
• Write a JavaScript function that takes user input and returns an escaped version for constructing dynamic regex patterns.

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