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

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.34/modules/angular2/src/directives/ng_if.ts#L3-L48">angular2/src/directives/ng_if.ts (line 3)</a>

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  Removes or recreates a portion of the DOM tree based on an {expression}.
  
  If the expression assigned to `ng-if` evaluates to a false value then the element
  is removed from the DOM, otherwise a clone of the element is reinserted into the DOM.
  
  # Example:
  
  ```
  <div *ng-if="errorCount > 0" class="error">
    <!-- Error message displayed when the errorCount property on the current context is greater
  than 0. -->
    {{errorCount}} errors detected
  </div>
  ```
  
  # Syntax
  
  - `<div *ng-if="condition">...</div>`
  - `<div template="ng-if condition">...</div>`
  - `<template [ng-if]="condition"><div>...</div></template>`
  
  

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  h2 Annotations
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    h3.annotation Directive
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        @Directive({selector: &#39;[ng-if]&#39;, properties: [&#39;ngIf&#39;]})


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    h3 constructor

    
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      code.
        constructor(viewContainer: ViewContainerRef, templateRef: TemplateRef)
    
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    h3 viewContainer

    
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    h3 templateRef

    
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    h3 prevCondition

    
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    h3 ngIf

    
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