JavaScript Strings
A string in JavaScript is a primitive data type that represents a sequence of characters. It is enclosed by single quotes (' '), double quotes (" "), or backticks (' ').
Example:
let name1
=
"Peter";
let name2
=
'Perker';
let greeting
=
`Hello ${name}!`;
String Methods
JavaScript has several built-in methods for manipulating strings.
length
The length method returns the length of a string.
Example:
let str
=
"Hello JavaScript";
console.log(str.length);
Output:
16
concat
The concat() method method is used to concatenate two or more strings.
Example:
let str1
=
"Hello";
let str2
=
" JavaScript";
console.log(str1.concat(str2));
Output:
Hello JavaScript
indexOf
The indexOf() method is used to find the index of a specific character in a string.
Example:
let str
=
"Hello JavaScript";
console.log(str.indexOf("J"));
Output:
6
replace
The replace() method replaces a string with another string.
Example:
let str = "Hello JavaScript";
console.log(str.replace("Hello", "I Love"));Output:
I Love JavaScript
toUpperCase and toLowerCase
The toUpperCase() and toLowerCase() methods are used to convert a string to uppercase or lowercase letters.
Example:
let str
=
"Hello JavaScript";
console.log(str.toUpperCase());
console.log(str.toLowerCase());
Output:
HELLO JAVASCRIPT
hello javascript