JavaScript RegExp Objects

The RegExp Object

In JavaScript, RegExp is a regular expression object with predefined properties and methods.

Using test()

The test() method is a RegExp expression method.

It searches a string for a pattern, and returns true or false, depending on the result.

The following example searches a string for the character "e":

Example

const pattern = /e/;

pattern.test("The best things in life are free!");

Since there is an "e" in the string, the output of the code above will be:

true

You don't have to put the regular expression in a variable first. The two lines above can be shortened to one:

/e/.test("The best things in life are free!");

Using exec()

The exec() method is a RegExp expression method.

It searches a string for a specified pattern, and returns the found text as an object.

If no match is found, it returns an empty (null) object.

The following example searches a string for the character "e":

Example

 /e/.exec("The best things in life are free!");

The RegExp.escape() Method

The RegExp.escape() method returns string where characters that belongs to the regular expression syntax are escaped.

This makes it possible to treat characters like +, *, ?, ^, $, (, ), [, ], {, }, |, and literally, and not as part of a regular expression.

Example

Create a regular expression that matches the string "[*]":

// Escape a text for to use as a regular expression

const safe = RegExp.escape("[*]";

// Build a new reglar expression

const regex = new RegExp(safe);

// Text to replace within

const oldText = "[*] is a web school.";

// Perform the replace

const newText = oldText.replace(regex, "Example");

Browser Support

RegExp.escape() is an ECMAScript 2025 feature.

JavaScript 2025 is fully supported in all modern browsers since May 2025:

See Also:

• JavaScript RegExp Tutorial
• JavaScript RegExp Flags
• JavaScript RegExp Character Classes
• JavaScript RegExp Meta Characters
• JavaScript RegExp Assertions
• JavaScript RegExp Groups
• JavaScript RegExp Quantifiers
• JavaScript RegExp Patterns
• JavaScript RegExp Methods