Insert HTML into View from AngularJS Controller

In this tutorial, we will see how to insert HTML into View from the AngularJS controller.

In AngularJS, when you need to dynamically insert HTML content into a view from a controller, you can encounter security errors due to the framework’s default behavior. To address this issue, you can use either $sce or the ngSanitize module. Additionally, creating a custom filter is an option to achieve this. Let’s explore these methods:

Method 1: Using `$sce`

This heading introduces the first method, which involves using the $sce service provided by AngularJS to safely insert HTML content into a view.

Now, follow the steps below to achieve this task.

Include ngSanitize

This step advises you to include the angular-sanitize.min.js file in your project. This file provides the ngSanitize module, which is necessary for securely handling HTML content in AngularJS.

<script src="lib/angular/angular-sanitize.min.js"></script>

Modify the Angular Module

Here, you’re instructed to modify your Angular module setup to include the ngSanitize module. This ensures that AngularJS recognizes and utilizes the sanitation features provided by ngSanitize.

angular.module('myApp', ['ngSanitize']);

Use $sce.trustAsHtml() in the Controller

In this step, you learn how to use the $sce.trustAsHtml() function within your controller. This function is used to mark a string as trusted HTML, allowing it to be safely inserted into the view.

angular.module('myApp').controller('MyController', ['$scope', '$sce',
    function ($scope, $sce) {
        $scope.thisCanBeusedInsideNgBindHtml = $sce.trustAsHtml(someHtmlVar);
    }]);

Bind HTML in the View

Finally, this step shows how to bind the HTML content to the view using the ng-bind-html directive. This directive is AngularJS’s way of securely inserting HTML content into the DOM.

<div ng-controller="MyController">
    <div ng-bind-html="thisCanBeusedInsideNgBindHtml"></div>
</div>

Method 2: Using ngSanitize Filter

This heading introduces the second method, which involves creating a custom filter using ngSanitize to securely insert HTML content into a view.

Here are the steps below to do this.

Create a Filter

Here, you’re instructed to create a custom filter that utilizes the $sce service to trust HTML content. This filter ensures that the HTML content is sanitized and safe to display in the view.

app.filter("trust", ['$sce', function($sce) {
    return function(htmlCode){
        return $sce.trustAsHtml(htmlCode);
    }
}]);

Apply the Filter in the View

In this step, you learn how to apply the custom filter created in Step 1 to bind HTML content to the view. This ensures that the HTML content is sanitized and securely displayed.

<div ng-bind-html="trusted_html_variable | trust"></div>

Note: Be cautious when using this filter with user input, as it may pose an XSS vulnerability.

Method 3: Shortest Way – Using ng-bind-html-unsafe (Deprecated)

This heading mentions an alternative method that is now deprecated. It advises against using ng-bind-html-unsafe due to security concerns and recommends using the $sce or ngSanitize approach instead.

<div ng-bind-html-unsafe="customHtml"></div>

Note: This method is deprecated, and it’s recommended to use the $sce or ngSanitize approach for security.

Method 4: Alternative Short Way – Using a Custom Filter

This heading introduces another alternative method, which involves creating a custom filter to trust HTML content. Similar to Method 2, this method allows you to securely insert HTML content into a view using a custom filter.

Create a filter to trust HTML content:

myApp.filter('unsafe', function($sce) { 
    return $sce.trustAsHtml; 
});

Apply the filter in your view:

<div ng-bind-html="customHtml | unsafe"></div>

These methods should help you insert HTML content into a view from an AngularJS controller while ensuring security and compliance with AngularJS version 1.x. Choose the method that best fits your project’s requirements and security considerations.

Method 1: Using $sce