AngularJS Expressions

Last modified on: November 24, 2024

<div class="flex-shrink-0 flex flex-col relative items-end">
<div>
<div class="pt-0">
<div class="gizmo-bot-avatar flex h-8 w-8 items-center justify-center overflow-hidden rounded-full">&nbsp;</div>
</div>
</div>
</div>
<div class="group/conversation-turn relative flex w-full min-w-0 flex-col agent-turn">
<div class="flex-col gap-1 md:gap-3">
<div class="flex max-w-full flex-col flex-grow">
<div class="min-h-8 text-message flex w-full flex-col items-end gap-2 whitespace-normal break-words [.text-message+&amp;]:mt-5" dir="auto" data-message-author-role="assistant" data-message-id="f24cb61a-d7b0-42ee-9e63-ff9176a1954e" data-message-model-slug="gpt-4o">
<div class="flex w-full flex-col gap-1 empty:hidden first:pt-[3px]">
<div class="markdown prose w-full break-words dark:prose-invert light">
<h3>AngularJS Expressions: Detailed Overview with Examples</h3>
<h4>Introduction</h4>
<p>AngularJS expressions are code snippets that are evaluated by AngularJS in the context of the current scope. These expressions are similar to JavaScript code but can be used in HTML templates. They are lightweight and designed to perform simple operations like binding data, performing calculations, and dynamically rendering content in the view.</p>
<hr />
<h4>Key Features of AngularJS Expressions</h4>
<ol>
<li><strong>Simplicity</strong>: Write expressions directly in HTML using double curly braces (<code>{{ }}</code>).</li>
<li><strong>Scope Context</strong>: Automatically binds to AngularJS <code>$scope</code> variables.</li>
<li><strong>No Side Effects</strong>: Expressions are pure; they do not modify application state.</li>
<li><strong>Filters</strong>: Easily format data within expressions.</li>
<li><strong>Safe Evaluation</strong>: AngularJS prevents expressions from accessing global objects (e.g., <code>window</code>, <code>document</code>).</li>
</ol>
<hr />
<h4>Basic Example of AngularJS Expressions</h4>
<p><strong>HTML Structure</strong>:</p>
<div class="contain-inline-size rounded-md border-[0.5px] border-token-border-medium relative bg-token-sidebar-surface-primary dark:bg-gray-950">
<div class="flex items-center text-token-text-secondary px-4 py-2 text-xs font-sans justify-between rounded-t-md h-9 bg-token-sidebar-surface-primary dark:bg-token-main-surface-secondary select-none">html</div>
<div class="sticky top-9 md:top-[5.75rem]">
<div class="absolute bottom-0 right-2 flex h-9 items-center">
<div class="flex items-center rounded bg-token-sidebar-surface-primary px-2 font-sans text-xs text-token-text-secondary dark:bg-token-main-surface-secondary">
<pre class="language-markup"><code>&lt;!DOCTYPE html&gt;
&lt;html&gt;
&lt;head&gt;
    &lt;title&gt;AngularJS Expressions Example&lt;/title&gt;
    &lt;script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.8.2/angular.min.js"&gt;&lt;/script&gt;
&lt;/head&gt;
&lt;body ng-app="expressionApp" ng-controller="expressionCtrl"&gt;
    &lt;h1&gt;AngularJS Expressions&lt;/h1&gt;
    &lt;p&gt;1 + 1 = {{ 1 + 1 }}&lt;/p&gt;
    &lt;p&gt;Message: {{ message }}&lt;/p&gt;
    &lt;p&gt;Full Name: {{ firstName + ' ' + lastName }}&lt;/p&gt;
&lt;/body&gt;

&lt;script&gt;
    var app = angular.module("expressionApp", []);
    app.controller("expressionCtrl", function($scope) {
        $scope.message = "Hello, AngularJS!";
        $scope.firstName = "John";
        $scope.lastName = "Doe";
    });
&lt;/script&gt;
&lt;/html&gt;
</code></pre>
</div>
</div>
</div>
</div>
<hr />
<h4>Advanced Example: Using Filters in Expressions</h4>
<p>Filters can be applied within expressions to format data.</p>
<p><strong>HTML Structure</strong>:</p>
<div class="contain-inline-size rounded-md border-[0.5px] border-token-border-medium relative bg-token-sidebar-surface-primary dark:bg-gray-950">
<div class="flex items-center text-token-text-secondary px-4 py-2 text-xs font-sans justify-between rounded-t-md h-9 bg-token-sidebar-surface-primary dark:bg-token-main-surface-secondary select-none">html</div>
<div class="sticky top-9 md:top-[5.75rem]">
<div class="absolute bottom-0 right-2 flex h-9 items-center">
<div class="flex items-center rounded bg-token-sidebar-surface-primary px-2 font-sans text-xs text-token-text-secondary dark:bg-token-main-surface-secondary">
<pre class="language-markup"><code>&lt;!DOCTYPE html&gt;
&lt;html&gt;
&lt;head&gt;
    &lt;title&gt;AngularJS Filters in Expressions&lt;/title&gt;
    &lt;script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.8.2/angular.min.js"&gt;&lt;/script&gt;
&lt;/head&gt;
&lt;body ng-app="filterApp" ng-controller="filterCtrl"&gt;
    &lt;h1&gt;AngularJS Filters&lt;/h1&gt;
    &lt;p&gt;Original Price: {{ price }}&lt;/p&gt;
    &lt;p&gt;Formatted Price: {{ price | currency }}&lt;/p&gt;
    &lt;p&gt;Uppercase Name: {{ name | uppercase }}&lt;/p&gt;
&lt;/body&gt;

&lt;script&gt;
    var app = angular.module("filterApp", []);
    app.controller("filterCtrl", function($scope) {
        $scope.price = 1234.56;
        $scope.name = "angular expressions";
    });
&lt;/script&gt;
&lt;/html&gt;
</code></pre>
</div>
</div>
</div>
</div>
<hr />
<h3>&nbsp;</h3>
</div>
</div>
</div>
</div>
</div>
</div>

Web Technology View More