Check an array of strings contains a substring in JavaScript

The string is the combination of the characters and a substring is the subset of a string. We will be given a substring and a string and we need to check whether the given substring is present in the given string or not.

These are the following ways to do this:

Method 1: Using includes() method and filter() method

First, we will create an array of strings, and then use includes() and filter() methods to check whether the array elements contain a sub-string or not.

Example: This example shows the implementation of the above-explained approach.

const arr = ['Geeks', 'gfg', 'GeeksforGeeks', 'abc'];
const substr = 'eks';

const subArr = arr.filter(str => str.includes(substr));

console.log(subArr);

[ 'Geeks', 'GeeksforGeeks' ]

Method 2: Using includes() method and some() method

First, we will create an array of strings, and then use includes() and some() methods to check whether the array elements contain a sub-string or not.

Example: This example shows the implementation of the above-explained approach.

const arr = ['Geeks', 'gfg', 'GeeksforGeeks', 'abc'];
const substr = 'eks';

const subArr = arr.some(str => str.includes(substr));

console.log(subArr);

true

Method 3: Using indexOf() method

In this approach, we are using indexOf() method that returns the index of the given value in the given collection.

Example: This example shows the implementation of the above-explained approach.

const arr = "geeksforgeeks"
const substr = 'eks';

const subArr = arr.indexOf(substr);

if (subArr) { console.log("true") }
else { console.log("false") }

true

Method 4: Using Lodash _.strContains() Method

In this example, we are using the Lodash _.strContains() method that return the boolean value true if the given value is present in the given string else it returns false.

Example: This example shows the implementation of the above-explained approach.

// Defining lodash contrib variable 
let _ = require('lodash-contrib');

let bool = _.strContains("abc", "a");

console.log("The String contains the "
    + "searched String : ", bool); 

Output:

The String contains the searched String : false

Method 5: Using a for of loop

Using a for of loop and indexOf iterates through each string in the array. It checks if the substring exists in each string using the indexOf method. If found (`indexOf` not equal to `-1`), it sets a flag indicating the substring’s presence.

Example: In this example we creates a new array subArr containing strings from arr that contain the substring ‘eks’ using a loop and indexOf.

const arr = ['Geeks', 'gfg', 'GeeksforGeeks', 'abc'];
const substr = 'eks';
let subArr = [];

for (let str of arr) {
    if (str.indexOf(substr) !== -1) {
        subArr.push(str);
    }
}

console.log(subArr); 

[ 'Geeks', 'GeeksforGeeks' ]