In this article, we will see the correct way to check for string equality in JavaScript. Whenever we need to compare the string we check for string equality by using different approaches. Strict equality operator is also one of the methods of comparison.
A few methods are explained below:
- Using strict equality operator
- Using double equals (==) operator
- Using String.prototype.localeCompare() method
- Using String.prototype.match() method
Method 1: Using strict equality operator
This operator checks for both value and type equality. it can be also called as strictly equal and is recommended to use it mostly instead of double equals
Example:
Javascript
const str1 = 'neveropen for neveropen' ; const str2 = 'neveropen for neveropen' ; if (str1 === str2) { console.log( 'The strings are equal ' ); } else { console.log( 'The strings are not equal' ); } |
Output:
The strings are equal
Method 2: Using double equals (==) operator
This operator checks for value equality but not type equality.
Example:
Javascript
const numStr = '42' ; if (numStr == 42) { console.log( 'The values are equal' ); } else { console.log( 'The values are not equal' ); } |
Output:
The strings are equal
Method 3: Using String.prototype.localeCompare() method
This method compares two strings and returns a value indicating whether one string is less than, equal to, or greater than the other in sort order.
Example:
Javascript
const str1 = 'hello' ; const str2 = 'neveropen for neveropen' ; const comparison = str1.localeCompare(str2); if (comparison === 0) { console.log( 'The strings are equal' ); } else { console.log( 'The strings are not equal' ); } |
Output:
The strings are not equal
Method 4: Using String.prototype.match() method
This method tests a string for a match against a regular expression and returns an array of matches.
Example:
Javascript
const str1 = 'hello neveropen' ; const str2 = 'hello neveropen' ; const match = str2.match(str1); if (match) { console.log( 'The strings are equal' ); } else { console.log( 'The strings are not equal' ); } |
Output:
The strings are equal