JavaScript switch statement

switch statement is used to perform different actions based on different conditions.

JavaScript switch statement

Use the switch statement to select one of multiple blocks of code to execute.

Syntax

switch(n)
{
case 1:
  执行代码块 1
break;
case 2:
  执行代码块 2
break;
default:
 n 与 case 1 和 case 2 不同时执行的代码
}

Working principle: First set the expression n (usually a variable). The value of the expression is then compared to the value of each case in the structure. If there is a match, the code block associated with the case is executed. Please use break to prevent the code from automatically running to the next case.

Example

Displays today’s week name. Please note that Sunday=0, Monday=1, Tuesday=2, etc.:

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>php中文网(php.cn)</title>
</head>
<body>
<p>点击下面的按钮来显示今天是周几：</p>
<button onclick="myFunction()">点击这里</button>
<p id="demo"></p>
<script>
    function myFunction(){
        var x;
        var d=new Date().getDay();
        switch (d){
            case 0:x="今天是星期日";
                break;
            case 1:x="今天是星期一";
                break;
            case 2:x="今天是星期二";
                break;
            case 3:x="今天是星期三";
                break;
            case 4:x="今天是星期四";
                break;
            case 5:x="今天是星期五";
                break;
            case 6:x="今天是星期六";
                break;
        }
        document.getElementById("demo").innerHTML=x;
    }
</script>
</body>
</html>

Run the program and try it

default Keywords

Please use the default keyword to specify what to do when the match does not exist:

Example

If today If it is not Saturday or Sunday, the default message will be output:

<html>
<head>
    <meta charset="utf-8">
    <title>php中文网(php.cn)</title>
</head>
<body>
<p>点击下面的按钮，会显示出基于今日日期的消息：</p>
<button onclick="myFunction()">点击这里</button>
<p id="demo"></p>
<script>
    function myFunction()
    {
        var x;
        var d=new Date().getDay();
        switch (d)
        {
            case 6:x="今天是星期六";
                break;
            case 0:x="今天是星期日";
                break;
            default:
                x="期待周末";
        }
        document.getElementById("demo").innerHTML=x;
    }
</script>
</body>
</html>

Run the program and try it

Continuing Learning

new file

<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>php中文网(php.cn)</title> </head> <body> <p>点击下面的按钮来显示今天是周几：</p> <button onclick="myFunction()">点击这里</button> <p id="demo"></p> <script> function myFunction(){ var x; var d=new Date().getDay(); switch (d){ case 0:x="今天是星期日"; break; case 1:x="今天是星期一"; break; case 2:x="今天是星期二"; break; case 3:x="今天是星期三"; break; case 4:x="今天是星期四"; break; case 5:x="今天是星期五"; break; case 6:x="今天是星期六"; break; } document.getElementById("demo").innerHTML=x; } </script> </body> </html>

submit Reset Code

Automatic operation

JavaScript switch statement

ElementaryImperial CMS enterprise imitation website tutorial

ElementaryNewbies with zero foundation in WordPress build personal blogs and corporate websites

ElementaryUltimate CMS zero-based website building instruction video

ElementaryFront-end project-Shangyou [HTML/CSS/JS technology comprehensive practice]

IntermediateVue3.0 from 0 to build a universal backend management system project practice

ElementaryZero-based front-end course [Vue advanced learning and practical application]

ElementaryWEB front-end tutorial [HTML5+CSS3+JS]

ElementaryQuick introduction to apipost

IntermediateVue3+TypeScript practical tutorial-enterprise-level project practice

ElementaryLet's briefly talk about starting a business in PHP

IntermediateVUE e-commerce project (front-end & back-end dual project actual combat)

ElementaryApipost practical application [api, interface, automated testing, mock]