JS Switch

Examples
例子

Switch statement[开关语句]
How to write a switch statement.
怎样写switch(开关)语句

The JavaScript Switch Statement
JS 开关语句

Syntax
语法

switch(n)
{
case 1:
  execute code block 1
  break    
case 2:
  execute code block 2
  break
default:

  code to be executed if n is
  different from case 1 and 2
}

This is how it works: First we have a single expression n (most often a variable), that is evaluated once. The value of the expression is then compared with the values for each case in the structure. If there is a match, the block of code associated with that case is executed. Use break to prevent the code from running into the next case automatically.
它是这样工作的:首先，有唯一的一个表达式 n (大多数为一个变量)，它是被赋过值的。 接下来表达式将与每个case(事件)进行比较。如果吻合就执行该事件内的代码块。使用break来防止代码执行后自动转向下一个事件。

Example
例子

<script type="text/javascript">
//You will receive a different greeting based
//on what day it is. Note that Sunday=0,
//Monday=1, Tuesday=2, etc.

var d=new Date()
theDay=d.getDay()
switch (theDay)
{
case 5:
  document.write("Finally Friday")
  break
case 6:
  document.write("Super Saturday")
  break
case 0:
  document.write("Sleepy Sunday")
  break
default:
  document.write("I'm looking forward to this weekend!")
}

</script>

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