JavaScript strings (String) object

JavascriptString Object

A String object is used to handle an existing block of characters.

JavaScript string

A string is used to store a series of characters like "John Doe".

A string can use either single or double quotation marks:

Example var carname= "Volvo XC60";
var carname= ' Volvo XC60 ';

You use the location (index) to access any character in the string:

Example Var character=carname[7];

The index of the string starts at zero, so the first character of the string is [0], the second character is [1], and so on.

You can use quotation marks in a string, as in the following example:

Example var answer= "It ' s Alright";
var answer= "He is called ' Johnny '";
var answer= ' He is called ' Johnny ';

Or you can use the escape character in the string to quote:

Example var answer= ' It ' s alright ';
var answer= "He is called" Johnny "";
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Strings (String)

String (string) to calculate the length of the string using length property:

Example var txt= "Hello world!";
document.write (txt.length);

var txt= "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
document.write (txt.length);
Try it» Find a string in a string

The string uses indexOf () to position the first occurrence of a specified character in a string:

Example var str= "Hello World, Welcome to the universe";
var n=str.indexof ("Welcome");
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If the corresponding character function is not found, return-1

The LastIndexOf () method starts at the end of the string to find where the string appears.

Content Matching

The match () function is used to find a specific character in a string and, if found, returns the character.

Example var str= "Hello world!";
document.write (Str.match ("World") + "<br>");
document.write (Str.match ("World") + "<br>");
document.write (Str.match ("world!"));
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Replace content

The Replace () method replaces some character with some characters in a string.

Example str= "Please visit microsoft!"
var n=str.replace ("Microsoft", "W3cschool");
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String Case Conversion

The string case conversion uses the function touppercase () / toLowerCase ():

Example var txt= "Hello world!"; String
var txt1=txt.touppercase (); TXT1 is txt converted to upper
var txt2=txt.tolowercase (); TXT2 is txt converted to lower
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String to Array

The string is converted to an array using the Strong>split () function:

Instance txt= "A,b,c,d,e"//String
Txt.split (","); Split on commas
Txt.split (""); Split on Spaces
Txt.split ("|"); Split on Pipe
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Special characters

In Javascript, you can use backslashes (\) to insert special symbols, such as apostrophes, quotation marks, and other special symbols.

Look at the following JavaScript code:

var txt= "We is the so-called" Vikings "from the north.";
document.write (TXT);

In JavaScript, the start and stop of a string use single or double quotation marks. This means that the above string will be cut into: We are the so-called

To resolve the above problems, you can use backslashes to escape quotation marks:

var txt= "We is the so-called \" Vikings\ "from the north.";
document.write (TXT);

JavaScript will output the correct text string: We are the "Vikings" from the so-called.

The following table lists other special characters that you can use to escape special characters by using backslashes:

Code	Output
\‘	Single quotation marks
\"	Double quotes
\\	Diagonal Bar
\ n	Line break
\ r	Enter
\ t	tab
\b	Space
\f	Page change

String properties and Methods

Property:

• Length
• Prototype
• Constructor

Method:

• CharAt ()
• charCodeAt ()
• Concat ()
• fromCharCode ()
• IndexOf ()
• LastIndexOf ()
• Match ()
• Replace ()
• Search ()
• Slice ()
• Split ()
• SUBSTR ()
• SUBSTRING ()
• toLowerCase ()
• toUpperCase ()
• ValueOf ()

JavaScript strings (String) object