Difference between ng-container and ng-template in AngularJS

Both ng-container and ng-template can be used to create responsive and dynamic components. Angular provides a set of structural directives that can be used with both ng-template and ng-container such as:

ng-if
ng-for
ng-switch.

These structural directives are used to alter the structure of the DOM by conditionally rendering the HTML elements.

Both ng-container and ng-template render the wrapped elements while hiding themselves but they both follow different mechanisms, these difference will be shown in the following article.

ng-template: Let’s try an example:

import { Component } from '@angular/core'; 
@Component({ 
  selector: 'app-root', 
  template: ` 
  <div style="text-align: center;"> 
    
  <!--no directive is used with ng-template--> 
    
  <ng-template> 
    <h1> 
      {{title}} 
    </h1> 
  </ng-template> 
  </div>  
  `, 
  styleUrls: [] 
}) 
export class AppComponent { 
  title = 'geeksforgeeks';  
} 

Yes, nothing will be rendered. When we check the HTML code, we will see:

It is because ng-template does not do anything on its own. It needs some rendering logic to render something.

Let’s try another example:

import { Component } from '@angular/core'; 
  
@Component({ 
  selector: 'app-root', 
  template: ` 
  <div style="text-align: center;"> 
    
  <!--this time we will add an 
 ng-if directive to ng-template.--> 
    
  <ng-template [ngIf]="datahide"> 
  <p> 
    {{ title }} 
  </p> 
  </ng-template> 
  </div>  
  `, 
  styleUrls: [] 
}) 
export class AppComponent { 
  title = 'geeksforgeeks';  
  datahide = true; 
} 

This time output will be like this:

In both the example, we can see template comments itself out, rendering the wrapped content conditionally.

ng-container: The ‘ng-container’ indeed shares some similarities with ‘ng-template’, like they both render the wrapped content while omitting themselves. But ng-container, on the other hand, is used when we use multiple structural directives and have no suitable parent wrapper. It does not require a structural directive to render the child elements unlike ng-template were using a structural directive was necessary.

Let’s see an example:

import { Component } from '@angular/core'; 
  
@Component({ 
  selector: 'app-root', 
  template: ` 
  <div style="text-align: center;"> 
    
  <!--ng-container without any structural directive--> 
    
  <ng-container> 
  <p> 
    {{ title }} 
  </p> 
  </ng-container> 
  </div>  
  `, 
  styleUrls: [] 
}) 
export class AppComponent { 
  title = 'geeksforgeeks';  
  datahide = true; 
} 

Now in this case, HTML was rendered even without any structural directive:

Let’s see what will happen if we wrap a ng-template inside a ng-container:

import { Component } from '@angular/core'; 
  
@Component({ 
  selector: 'app-root', 
  template: ` 
  <div style="text-align: center;"> 
    
  <!--ng-container used as wrapper for ng-template--> 
    
  <ng-container> 
  <ng-template [ngIf]="datahide"> 
  <p> 
    {{ title }} 
  </p> 
  </ng-template> 
  </ng-container> 
  </div>  
  `, 
  styleUrls: [] 
}) 
export class AppComponent { 
  title = 'geeksforgeeks';  
  datahide = true; 
} 

ng-container successfully wraps a ng-template:

To conclude, we can say that both the ng-container and ng-template are used to wrap HTML elements. They differ in their mechanisms. Also, multiple structural directives are not possible inside ng-template but ng-container can be used to wrap multiple elements containing different structural directives so it is a perfect container.

My Personal Notes

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