Understanding ng-if, ng-switch and ng-repeat directives

Shailendra Chauhan  Print   1 min read  
30 Dec 2014
 
Intermediate
69.9K

AngularJS provides you ng-if, ng-switch directives to display HTML elements based on conditions or cases. ng-repeat directive is used to generate HTML from a collection of items.

ng-if

This directive can add / remove HTML elements from the DOM based on an expression. If the expression is true, it add HTML elements to DOM, otherwise HTML elements are removed from the DOM.

<div ng-controller="MyCtrl">
 <div ng-if="data.isVisible">ng-if Visible</div>
</div>

<script>
 var app = angular.module("app", []);
 app.controller("MyCtrl", function ($scope) {
 $scope.data = {};
 $scope.data.isVisible = true;
 });
</script>

ng-switch

This directive can add / remove HTML elements from the DOM conditionally based on scope expression.

<div ng-controller="MyCtrl">
 <div ng-switch on="data.case">
 <div ng-switch-when="1">Shown when case is 1</div>
 <div ng-switch-when="2">Shown when case is 2</div>
 <div ng-switch-default>Shown when case is anything else than 1 and 2</div>
 </div>
</div>

<script>
 var app = angular.module("app", []);
 app.controller("MyCtrl", function ($scope) {
 $scope.data = {};
 $scope.data.case = true;
 });
</script>

ng-repeat

This directive is used to iterate over a collection of items and generate HTML from it.

<div ng-controller="MyCtrl">
 <ul>
 <li ng-repeat="name in names">
 {{ name }}
 </li>
 </ul>
</div>

<script>
 var app = angular.module("app", []);
 app.controller("MyCtrl", function ($scope) {
 $scope.names = ['Shailendra', 'Deepak', 'Kamal'];
 });
</script>

What do you think?

I hope you will enjoy the ng-if, ng-switch and ng-repeat directives in AngularJS while developing your app with AngularJS. I would like to have feedback from my blog readers. Your valuable feedback, question, or comments about this article are always welcome.

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