You can find a substring in a string using a classic indexOf() or the new ES6 includes() in Javascript. It’s very easy to do in Javascript programming. If you want a search particular word like a “Hello” then you have to use a regex (regular expression).
Methods to Check if a string contains substring JavaScript
- indexOf()
- includes()
1. String.includes() Method
This method is introduced in ES6, it’s very easy to use and returns a boolean value. See below example only support ES6.
<!DOCTYPE html>
<html>
<body>
<p id="c1"></p>
<p id="c2"></p>
<script>
// ES6 only
var str = "EyeHunts";
var check1 = str.includes('Eye');
var check2 = str.includes('ABC');
document.getElementById("c1").innerHTML = check1;
document.getElementById("c2").innerHTML = check2;
</script>
</body>
</html> Output:
2. String.indexOf() Method
The indexof() method returns a substring is found, it returns the index of the character that starts the string otherwise return -1.
<!DOCTYPE html>
<html>
<body>
<p id="c1"></p>
<p id="c2"></p>
<script>
var str = "EyeHunts Tutorial";
if (str.indexOf('Hunts') > -1) { // returns `-1` if it is not present.
// display this
document.getElementById("c1").innerHTML = str.indexOf('Hunts');
} else {
document.getElementById("c2").innerHTML = "not found";
}
</script>
</body>
</html> Output: 3
Note:
includesdoesn’t have Internet Explorer support, though. In ECMAScript 5 or older environments, useString.prototype.indexOf.- Both
includes()andindexOf()method is case sensitive and also supports the offset parameter:
Do comment if you knew another method to find substring or have any doubts.
Note: The Examples are tested on Safari browser (Version 12.0.2) and Chrome.
OS: macOS 10.14 Mojave
Code: HTML 5 Version