Question

How to use switch case (multiple-choice selection) in JavaScript

Answer 1

var n = 2;        

switch (n) 
{
    case 1:
        document.write("One");
        break;
    case 2:
        document.write("Two");
        break;
    case 3:
        document.write("Three");
        break;
} 

/*
run:

Two   

*/

 

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Answer 2

// note: no break will enter to all cases from the start case
// the start case depend on the input n, if n == 2 start case is 2 (case 2:)         
        
var n = 2;        

switch (n) 
{
    case 1:
        document.write("One <br />");
        //break;
    case 2:
        document.write("Two <br />");
        //break;
    case 3:
        document.write("Three <br />");
        //break;
    case 4:
        document.write("Four <br />");
        //break;
} 

/*
run:

Two
Three
Four   

*/

 

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Answer 3

var n = 10;        

switch (n) 
{
    case 1:
        document.write("One <br />");
        break;
    case 2:
        document.write("Two <br />");
        break;
    case 3:
        document.write("Three <br />");
        break;
    default:
        document.write("n is not 1, 2, or 3 <br />");
} 

/*
run:

n is not 1, 2, or 3  

*/

 

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Answer 4

// no output without default if n is not 1, 2, or 3
        
var n = 10;        

switch (n) 
{
    case 1:
        document.write("One <br />");
        break;
    case 2:
        document.write("Two <br />");
        break;
    case 3:
        document.write("Three <br />");
        break;
} 

/*
run:

*/

 

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Answer 5

var s = "dan";        

switch (s) 
{
    case "tom":
        document.write("Tom <br />");
        break;
    case "rachel":
        document.write("Rachel <br />");
        break;
    case "dan":
        document.write("Dan <br />");
        break;
    default:
        document.write("default case <br />");
} 

/*
run:

Dan 

*/

 

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