JavaScript RegExp multiline
Syntax & Examples

RegExp.multiline property

The multiline property of the RegExp object in JavaScript indicates whether the 'm' flag, which enables multiline searching, is set. This property is read-only.

Syntax of RegExp.multiline

The syntax of RegExp.multiline property is:

RegExp.prototype.multiline

This multiline property of RegExp whether or not to search in strings across multiple lines. This property is read-only.

Return Type

RegExp.multiline returns value of type Boolean.


✐ Examples

1 Checking if the multiline property is enabled

In JavaScript, we can check if the 'm' flag is enabled for a RegExp object by accessing the multiline property.

For example,

  1. We create a RegExp object regex with the 'm' flag /^abc/m.
  2. We check the multiline property of regex to see if it is true.
  3. We log the result to the console.

JavaScript Program

const regex = /^abc/m;
const isMultilineEnabled = regex.multiline;
console.log(isMultilineEnabled);

Output

true

2 Comparing multiline property with and without the 'm' flag

In JavaScript, we can compare the multiline property of RegExp objects with and without the 'm' flag.

For example,

  1. We create a RegExp object regexWithM with the 'm' flag /^abc/m.
  2. We create another RegExp object regexWithoutM without the 'm' flag /^abc/.
  3. We check the multiline property of both objects and log the results to the console.

JavaScript Program

const regexWithM = /^abc/m;
const regexWithoutM = /^abc/;
console.log(regexWithM.multiline); // true
console.log(regexWithoutM.multiline); // false

Output

true
false

3 Using multiline property in conditional statements

In JavaScript, we can use the multiline property in conditional statements to perform different actions based on whether the 'm' flag is enabled.

For example,

  1. We create a RegExp object regex with the 'm' flag /^abc/m.
  2. We check the multiline property of regex in an if statement.
  3. If the property is true, we log 'Multiline searching is enabled.' to the console; otherwise, we log 'Multiline searching is not enabled.'.

JavaScript Program

const regex = /^abc/m;
if (regex.multiline) {
  console.log('Multiline searching is enabled.');
} else {
  console.log('Multiline searching is not enabled.');
}

Output

Multiline searching is enabled.

Summary

In this JavaScript tutorial, we learned about multiline property of RegExp: the syntax and few working examples with output and detailed explanation for each example.