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

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p.location-badge.
exported from <a href="/angular2/directives.html">angular2/directives</a>
defined in <a href="https://github.com/angular/angular/tree/master/modules/angular2/src/directives/switch.js#L39">angular2/src/directives/switch.js (line 39)</a>
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The `Switch` directive is used to conditionally swap DOM structure on your template based on a
scope expression.
Elements within `Switch` but without `SwitchWhen` or `SwitchDefault` directives will be
preserved at the location as specified in the template.
`Switch` 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 **`[switch]="..."` attribute**),
define any inner elements inside of the directive and place a `[switch-when]` attribute per
element.
The when attribute is used to inform Switch 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 [switch]="expression">
<template [switch-when]="whenExpression1">...</template>
<template [switch-when]="whenExpression1">...</template>
<template [switch-default]>...</template>
</ANY>
```
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