JavaScript String Methods Cheat Sheet PDF

1). String.indexOf()

This method will return the index within the string of the first occurrence of the specified string value. And it will return -1 if not found.

const str = "Geeks Help";

let strIndex = str.indexOf("Help");

console.log(strIndex);

Output: 6

2). String.lastIndexOf()

Returns the index within the string of the last occurrence of the specified value and it will return -1 if not found.

const str = "Geeks Help";

let lastIndex = str.lastIndexOf("Geeks");

console.log(lastIndex);

Output: 0

3). String.match()

Returns a list of matches of a regular expression against a string.

const str = "Hello World";

let strMatch = str.match(/[A-Z]/);

console.log(strMatch);

Output: ['H', index: 0, input: 'Hello World', groups: undefined]

4). String.charAt()

Returns a string representing the character at the given index.

const str = "Hello World";

let strChar = str.charAt(0);

console.log(strChar);

Output: H

5). String.concat()

It is used for string concatenation and it returns a new string.

const str1 = "Geeks ";

const str2 = "Help";

let newString = str1.concat(str2);

console.log(newString);

Output: Geeks Help

6). String.endsWith()

It returns true if the string contains the given string value otherwise it returns false

const siteStr= "Geeks Help";

const containStr = siteStr.endsWith("World");

console.log(containStr);

Output: false

7). String.toLowerCase()

It is used to convert the string to lowercase characters and returns a new string.

const str = "Geeks Help";

let lowerStr = str.toLowerCase();

console.log(lowerStr);

Output: geeks help

8). String.toUpperCase()

It is used to convert the string to uppercase characters and returns a new string.

const str = "Geeks Help";

let upperStr = str.toUpperCase();

console.log(upperStr);

Output: GEEKS HELP

9). String.toString()

This string method returns the string representation of the specified object.

const str = new String("Geeks Help");

let strToString= str.toString();

console.log(strToString);

Output: Geeks Help

10). String.matchAll()

This string method returns a list of matches of a regular expression against a string.

const str = "Hello World";

let strMatch = str.matchAll(/[A-Z]/g);

console.log(strMatch);

Output: Object [RegExp String Iterator] {}

11). String.repeat()

This method creates copies of the string according to the specified number and returns a new string.

const str = "Geeks ";

let repeatStr = str.repeat(3);

console.log(repeatStr);

Output: Geeks Geeks Geeks

12). String.replace()

It replaces the first match of a regular expression in the string replace by a new character and returns a new string.

const str = "Geeks Help";

let replaceStr = str.replace("e", "#");

console.log(replaceStr);

Output: G#eks Help

13). String.slice()

This method returns a new string containing the characters of the string from the given index to the end of the string.

const str = "Geeks Help";

let strSlice = str.slice(6);

console.log(strSlice);

Output: Help

14). String.split()

This method returns an array of strings split at the given index.

const str = "Geeks Help";

let strSplit = str.split(" ");

console.log(strSplit);

Output: [ 'Geeks', 'Help' ]

15). String.startsWith()

This string method returns true if the string starts with the given string, otherwise, it returns false.

const str = "Geeks Help";

let strStarts = str.startsWith("Raju");

console.log(strStarts);

Output: false

16). String.trim()

The trim() method removes whitespace from both sides of a string. And it returns a new string.

const str = "  Geeks Help";

let strTrim = str.trim();

console.log(strTrim);

Output: Geeks Help

17). String.trimStart()

This string method removes whitespace from the beginning of a string.

const str = "  Geeks Help ";

let trimStart = str.trimStart();

console.log(trimStart);

Output: Geeks Help

18). String.trimEnd()

This string method removes whitespace from the end of a string.

const str = "  Geeks Help  ";

let trimEnd = str.trimEnd();

console.log(trimEnd);

Output:      Geeks Help

JavaScript String Methods Cheat Sheet PDF: Download Now