What is the correct way to check for string equality in JavaScript ?

In JavaScript, there are different ways to check for string equality depending on what you’re trying to achieve. A few methods are explained below:

• Using the triple equals (===) operator
• Using the double equals (==) operator
• Using the String.prototype.localeCompare() method
• Using the String.prototype.match() method

Using the triple equals (===) 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 = 'geeks for geeks';
const str2 = 'geeks for geeks';

if (str1 === str2) {
  console.log('The strings are equal ');
} else {
  console.log('The strings are not  equal');
}

Output:

The strings are equal 

Using the 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 

Using the 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 = 'geeks for geeks';

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

Using the 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 geeks';
const str2 = 'hello geeks';

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