Check if string includes a substring Javascript (Multiple Methods)

September 28, 2022

If you're working with strings in JavaScript, it's often useful to know whether or not a string includes a particular substring. For example, you might want to check if a string contains a URL or a specific word. In this article, we will show you different methods to check that.

Check if string includes a substring Javascript

To check whether a String contains a substring you can:

Get the string and substring variables.
Use string.includes(sub_string) - It will return true if the substring exists in the string else false.

# Method 1: Using includes() function

The String.includes() function in Javascript allows you to check if a string includes a specified substring. This is a useful function to know when you need to check if a string contains a certain word or phrase.

const str = "Devsheet";
const subStr = "evs";

if (str.includes(subStr)) {
    console.log("Included");
} else {
    console.log("Not included");
}

Output

Included

Live Demo

The above code is checking if the string "Devsheet" includes the substring "evs". If it does, it will print "Included" to the console. Otherwise, it will print "Not included".

# Method 2: Using indexOf() function

If you need to check if a string includes a certain substring in JavaScript, you can use the indexOf() method. This method returns the index of the first occurrence of the substring, or -1 if the substring is not found.

const str = "Devsheet";
const subStr = "evs";

if (str.indexOf(subStr) !== -1) {
    console.log("Included");
} else {
    console.log("Not included");
}

Output

Included

Live Demo

In the above code example, we are using String.indexOf() function to check whether a string contains a substring.

Conclusion

These were some code examples that can be used to check whether a string includes a substring or not. We explained different methods in order to do that. If you have more methods for the same then you can also contribute here.

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