JavaScript Common Methods Part 2- Strings

Strings

Now let’s take a look at some of the most commonly used methods on strings available on JS. One important thing to note here is that all these methods are case sensitive, so be cautious when you use them in such scenarios.

1. startsWith()

Yes, you guessed it right. It tells you if a given string starts with a particular substring.

const str = 'Hello world, welcome to the javascript.';

console.log(str.startsWith('Hello')); // true

console.log(str.startsWith('Help'));  // false

2. endsWith()

Obviously there is an endsWith() as well. It returns true if a given string starts with a particular substring, and false otherwise.

const str = 'Hello world, welcome to the javascript.';

console.log(str.endsWith('javascript.')); // true

console.log(str.endsWith('hello'));       // false

3. includes()

includes() method quickly checks if the string includes a given substring and returns a corresponding boolean value.

var str = "Hello world, welcome to the universe.";

console.log(str.includes("world")); // true

console.log(str.includes("test"));  // false

String Methods List

1. charAt()  -  Returns the character at the specified index (position)
2. charCodeAt()  -  Returns the Unicode of the character at the specified index
3. concat()  -  Joins two or more strings, and returns a new joined strings
4. endsWith()  -  Checks whether a string ends with specified string/characters
5. fromCharCode() - Converts Unicode values to characters
6. includes() -   Checks whether a string contains the specified string/characters
7. indexOf() -   Returns the position of the first found occurrence of a specified value in a string
8. lastIndexOf()  -  Returns the position of the last found occurrence of a specified value in a string
9. localeCompare()  -  Compares two strings in the current locale
10. match() -   Searches a string for a match against a regular expression, and returns the matches
11. repeat() -   Returns a new string with a specified number of copies of an existing string
12. replace() -   Searches a string for a specified value, or a regular expression, and returns a new string where the specified values are replaced
13. search()  -  Searches a string for a specified value, or regular expression, and returns the position of the match
14. slice()  -  Extracts a part of a string and returns a new string
15. split() -   Splits a string into an array of substrings
16. startsWith() -   Checks whether a string begins with specified characters
17. substr()  -  Extracts the characters from a string, beginning at a specified start position, and through the specified number of character
18. substring()  -  Extracts the characters from a string, between two specified indices
19. toLocaleLowerCase() -   Converts a string to lowercase letters, according to the host's locale
20. toLocaleUpperCase()  -  Converts a string to uppercase letters, according to the host's locale
21. toLowerCase() -   Converts a string to lowercase letters
22. toString()  -  Returns the value of a String object
23. toUpperCase()  -  Converts a string to uppercase letters
24. trim()  -  Removes whitespace from both ends of a string
25. valueOf()  -  Returns the primitive value of a String object