angular-cn/public/docs/js/latest/api/directives/NgSwitch-class.jade

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p.location-badge.
exported from <a href='../directives'>angular2/directives</a>
defined in <a href="https://github.com/angular/angular/tree/2.0.0-alpha.32/modules/angular2/src/directives/ng_switch.ts#L19-L135">angular2/src/directives/ng_switch.ts (line 19)</a>
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The `NgSwitch` directive is used to conditionally swap DOM structure on your template based on a
scope expression.
Elements within `NgSwitch` but without `NgSwitchWhen` or `NgSwitchDefault` directives will be
preserved at the location as specified in the template.
`NgSwitch` simply chooses nested elements and makes them visible based on which element matches
the value obtained from the evaluated expression. In other words, you define a container element
(where you place the directive), place an expression on the **`[ng-switch]="..."` attribute**),
define any inner elements inside of the directive and place a `[ng-switch-when]` attribute per
element.
The when attribute is used to inform NgSwitch which element to display when the expression is
evaluated. If a matching expression is not found via a when attribute then an element with the
default attribute is displayed.
# Example:
```
<ANY [ng-switch]="expression">
<template [ng-switch-when]="whenExpression1">...</template>
<template [ng-switch-when]="whenExpression1">...</template>
<template ng-switch-default>...</template>
</ANY>
```
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h2 Members
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h3 constructor
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constructor()
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h3 ngSwitch
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