How Can I Define Strings In JavaScript With Examples

admin_img Posted By Bajarangi soft , Posted On 21-09-2020

JavaScript strings are used to hold data and that can be represented in text form.

How Can I Define Strings In JavaScript With Examples

JavaScript Strings

A JavaScript string is zero or more characters written inside quotes and You can also use single or double quotes:
Example(1)

<script>
    //You can use quotes inside a string, as long as they don't match the quotes surrounding the string.
    var first = " am first";
    var second = "am second ";
    var third = 'am third';

    document.getElementById("demo").innerHTML =
        first + "<br>" + second + "<br>" + third;
</script>
 

String Length

To find the length of a string, use the built-in length property:

var txt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
var string_length = txt.length;
 

Escape Character

Because strings must be written within quotes, JavaScript will misunderstand this string:

var x = "We are learning about "Java Script" from BajarangiSoft.";
 

The string will be chopped to "We are the so-called ".

The solution to avoid this problem, is to use the backslash escape character.

The backslash (\) escape character turns special characters into string characters:

Code Result Description
\' ' Single quote
\" " Double quote
\\ \ Backslash
 

 

Example(2)
The sequence \"  inserts a double quote in a string:

var x = "We are learning about  \"Java Script\" in BajarangiSoft site.";
 

Example(3)
The sequence \'  inserts a single quote in a string:

var x = 'It\'s alright.';


Example(4)
The sequence \\  inserts a backslash in a string:

var x = "The character \\ is called backslash.";


Six other escape sequences are valid in JavaScript:
 
Code Result
\b Backspace
\f Form Feed
\n New Line
\r Carriage Return
\t Horizontal Tabulator
\v Vertical Tabulator
 

Breaking Long Code Lines

For best readability, programmers often like to avoid code lines longer than 80 characters.

Example(1)

//If a JavaScript statement does not fit on one line, the best place to break it is after an operator:

document.getElementById("demo").innerHTML =
"Shiva Kumar!";


//You can also break up a code line within a text string with a single backslash:

document.getElementById("demo").innerHTML = "Shiva \
Kumar!";

// The \ method is not the preferred method. It might not have universal support.
Some browsers do not allow spaces behind the \ character.

// A safer way to break up a string, is to use string addition:

document.getElementById("demo").innerHTML = "Shiva " +
"Kumar!";
 

Strings Can be Objects

Normally, JavaScript strings are primitive values, created from literals:

var firstName = "shiva";

But strings can also be defined as objects with the keyword new:

var firstName = new String("shiva");
 

<script>
    var x = "shiva";        // x is a string
    var y = new String("shiva");  // y is an object

    document.getElementById("demo").innerHTML =
        typeof x + "<br>" + typeof y;
</script>
 

Complete code of string with java script 

<!DOCTYPE html>
<html>
<head>
    <title>JavaScript string</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
</head>
<style>
    h3{
        color:red;
    }
</style>
<body>
<div class="container">
    <br>
    <br>
    <div class="text-center">
        <h1>JavaScript String</h1>
    </div>
    <br>
        <div class="well">
            <h1 id="demo"></h1>
        </div>
    <br>
</div>
</body>
</html>
<script>
    //You can use quotes inside a string, as long as they don't match the quotes surrounding the string.
    var first = " am first";
    var second = "am second ";
    var third = 'am third';

    document.getElementById("demo").innerHTML =
        first + "<br>" + second + "<br>" + third;
</script>

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