Microsoft® JScript™ switch Statement | Language Reference Version 3

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##### Description

> Enables the execution of one or more statements when a specified expression's value matches a label.

##### Syntax

> switch (expression) {
> case label :
> statementlist
> case label :
> statementlist
> ...
> default :
> statementlist
> }

> The switch statement syntax has these parts:

> Part | Description
> expression | The expression to be evaluated.
> label | An identifier to be matched against expression. If label === expression, execution starts with the statementlist immediately after the colon, and continues until it encounters either a break statement, which is optional, or the end of the switch statement.
> statementlist | One or more statements to be executed.

##### Remarks

> Use the default clause to provide a statement to be executed if none of the label values matches expression. It can appear anywhere within the switch code block.

> Zero or more label blocks may be specified. If no label matches the value of expression, and a default case is not supplied, no statements are executed.

> Execution flows through a switch statement as follows:

> 1. Evaluate expression and look at label in order until a match is found.
> 2. If a label value equals expression, execute its accompanying statementlist.
>    Continue execution until a break statement is encountered, or the switch statement ends. This means that multiple label blocks are executed if a break statement is not used.
> 3. If no label equals expression, go to the default case. If there is no default case, go to last step.
> 4. Continue execution at the statement following the end of the switch code block.
> The following example tests an object for its type:

> >     function MyObject() {
> >     ...}
> >     switch (object.constructor){
> >     	case Date:
> >     	...
> >     	case Number:
> >     	...
> >     	case String:
> >     	...
> >     	case MyObject:
> >     	...
> >     	default:
> >     	...
> >     }

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