JavaScript switch case

JavaScript switch case: The Else Statement allows us to choose between TRUE or FALSE. When there are more than two options, we use the Nested If Statement. Say, What if we have ten alternatives to choose from? if we use Nested If, the programming logic will be difficult to understand. Here, switch statements and Else if can handle these types of problems effectively.

The working functionality of this is almost the same as if condition. As we said before, the Switch statement in JavaScript may have n number of cases. So, the switch case compares the expression value with the values assigned in the case statements.

If both the values (expression and case value) match, then the code block present in that case statement will execute. Let us see the syntax of the switch case in Javascript for a better understanding.

Syntax

The syntax of it is as follows:

Switch(expression) 
{
 Case Option 1:
    //Execute these when the expression result match Option 1
    break;
 Case Option 2:
    //Execute these when the expression result match Option 2
    break;
 Case Option 3:
    //Execute these when the expression result match Option 3
    break;
    ......
 Case Option N:
    //Execute when the result of expression match Option N
    break;
 Default:
    //Execute when the result of expression Not matching with any Option
    break;
}

The expression should be either integer or characters (We can write the expression as n/2…. also, but the result should be an integer). Option 1, Option 2…… are constants. It will only accept integers or characters, whereas the Else if block also accepts decimal values (2.3, 3.5, etc.).

The Switch Case allows us to add a default case. If the variable value does not match any of the case blocks, then the code present in the default will be executed. The Break statement is useful to come out from it. Otherwise, all the statements in the switch condition will execute. Whenever a break is encountered, the execution flow would directly come out of it.

JavaScript switch statement Example

This program allows us to use Arithmetic Operators to perform arithmetic operations using Switch Case. Please refer to JS Else, Nested If, and Break statement articles in JavaScript.

<!DOCTYPE html>
<html>
<head>
    <title> JavaScriptSwitchCase </title>
</head>
 <h1> JavaScriptSwitchCase </h1>
<body>
<script>
    var opertor = '*';
    var number1 = 10, number2 = 2;
    switch (opertor)
    {
        case '+':
            document.write("Addition of two numbers is: " + (number1 + number2));
            break;
        case '-':
            document.write("Subtraction of two numbers is: " + (number1 - number2));
            break;           
        case '*':
            document.write("Multiplication of two numbers is: " + (number1 * number2));
            break;
        case '/':
            document.write("Division of two numbers is: " + (number1 / number2));
            break;
        case '%':
            document.write("Module of two numbers is: " + (number1 % number2));
            break;
        default:
            document.write("<b> You have entered Wrong operator </b>");
            document.write("<br \> Please enter Correct operator such as +, -, *, /, %");
    }
</script>
</body>
</html>

OUTPUT 1: Here, we assigned * as the operator variable.

JavaScript Switch Case 1

Output 2: Let us change the operator from valid to the wrong operator (var operator = ‘//’;) to check the default value.

You have entered Wrong operator
Please enter Correct operator such as +, -, *, /, %