Skip to content
Related Articles

Related Articles

Switch Case in JavaScript

View Discussion
Improve Article
Save Article
Like Article
  • Difficulty Level : Easy
  • Last Updated : 20 Jun, 2022

We have learned about decision-making in JavaScript using if-else statements in our previous article on if-else statements in JavaScript. We have seen in our previous article that we can use the if-else statements to perform actions based on some particular condition. That is if a condition is true then perform some task or else if the condition is false then execute some other task. 
The switch case statement in JavaScript is also used for decision-making purposes. In some cases, using the switch case statement is seen to be more convenient than if-else statements. Consider a situation when we want to test a variable for hundred different values and based on the test we want to execute some task. Using if-else statements for this purpose will be less efficient than switch-case statements and also it will make the code look messy.
The switch case statement is a multiway branch statement. It provides an easy way to dispatch execution to different parts of code based on the value of the expression.
Syntax
 

switch (expression)
{
    case value1:
        statement1;
        break;
    case value2:
        statement2;
        break;
    .
    .
    case valueN:
        statementN;
        break;
    default:
        statementDefault;
}

Explanation: 
 

  • expression can be of type numbers or strings.
  • Duplicate case values are not allowed.
  • The default statement is optional. If the expression passed to switch does not match with the value in any case then the statement under default will be executed.
  • The break statement is used inside the switch to terminate a statement sequence.
  • The break statement is optional. If omitted, execution will continue on into the next case.
  • Cases are compared strictly.

Flowchart
 

Example: 
 

JavaScript




<script type = "text/javascript">
 
    // JavaScript program to illustrate switch-case
    let i = 9;
   
    switch (i) 
    {
       case 0:
           console.log("i is zero.");
           break;
       case 1:
           console.log("i is one.");
           break;
       case 2:
           console.log("i is two.");
           break;
       default:
           console.log("i is greater than 2.");
    }
 
</script>

Output: 
 

i is greater than 2.

 

My Personal Notes arrow_drop_up
Recommended Articles
Page :

Start Your Coding Journey Now!