What is Angular Expression ?
Last Updated :
24 Apr, 2025
Angular is a great, reusable UI (User Interface) library for developers that help in building attractive, and steady web pages and web application. In this article, we will learn about Angular expression.
Angular Expression
An Angular Expression is a code snippet that can be simple or complex JavaScript-like code, like, the variable references, function calls, operators, and filters, etc., written within double curly braces {{ }} in order to evaluate & display dynamic values or perform calculations in the template.
Different Use Cases of Angular Expressions
Angular expressions are commonly used for various purposes, which are described below:
- Displaying Data: Angular expressions are extremely useful for displaying data obtained from variables or properties within templates.
- Performing Calculations: Expressions allow us to perform calculations and display the results dynamically.
- Conditional Rendering: Angular expressions can be used with directives like ng-if to conditionally render elements based on data conditions.
- Filtering Data: We can use Angular filters in expressions to format and filter data before displaying it.
- Event Handling: It can be used to handle user interactions and trigger actions in response to events.
Syntax
In the below syntax, the msg property is bound to the <p> element and its value will be displayed.
// app.component.html
<p> {{ mymsg }} </p>
// app.component.ts
export class AppComponent {
mymsg = 'Hello, Geek!';
}
ApproachÂ
There are different approaches to implementing the Angular Expression, among which the most commonly used approach are:
- By Interpolation
- By creating the Custom Directives
We'll explore both the approaches & understand their basic implementation through the examples.
By Interpolation
This is the most common and used method to use angular expression. In this, we use the {{ }} brackets to enclose the expressions within it. Interpolation is a way to transfer the data from a TypeScript code to an HTML template (view), i.e. it is a method by which we can put an expression in between some text and get the value of that expression.
Example: The below example demonstrates the basic usage of Expressions in the Angular application.
JavaScript
// app.component.ts
import { Component } from '@angular/core';
@Component({
selector: 'app-root',
template: `
<h1>Welcome to {{ appName }}</h1>`,
})
export class AppComponent {
appName = 'GeeksforGeeks';
}
// app.module.ts
import { NgModule } from '@angular/core';
import { BrowserModule }
from '@angular/platform-browser';
import { AppComponent } from './app.component';
@NgModule({
// Add your component to the declarations array
declarations: [AppComponent],
imports: [BrowserModule],
// Set your component as the root component
bootstrap: [AppComponent],
})
export class AppModule { }
<!-- index.html -->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>GFG App</title>
</head>
<body>
<!-- Include the root component here -->
<app-root></app-root>
</body>
</html>
Output:
By creating the Custom Directives
Another approach for using expressions in Angular is to use directives, like ngFor or ngModel, etc. to create custom directives, in order to bind expressions to specific element properties or events.
Example: The below example demonstrates the usage of expressions with the custom directive, in order to bind in the Angular application. Here, we are using the directive binding with [textContent] for displaying the geekName, geekCourse, etc along with the standard property binding using our first approach interpolation to display the geekRank property.
JavaScript
// gfg-profile.component.ts
import { Component } from '@angular/core';
@Component({
selector: 'app-gfg-profile',
template: `
<h2>GeeksforGeeks Profile</h2>
<div>
<p>Geek name:
<span [textContent]="geekName"></span></p>
<p>Course:
<span [textContent]="geekCourse"></span></p>
<p>Rank: <span>{{ geekRank }}</span></p>
</div>`,
})
export class GfgProfileComponent {
geekName = 'Tarun Singh';
geekCourse = 'DSA Self Paced';
geekRank = 5;
}
// app.module.ts
import { NgModule } from '@angular/core';
import { BrowserModule }
from '@angular/platform-browser';
import { GfgProfileComponent }
from './gfg-profile/gfg-profile.component';
@NgModule({
declarations: [GfgProfileComponent],
imports: [BrowserModule],
bootstrap: [GfgProfileComponent],
})
export class AppModule { }
<!-- index.html -->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>gfg</title>
</head>
<body>
<!-- Include the Custom Component here -->
<app-gfg-profile></app-gfg-profile>
</body>
</html>
Output:
Similar Reads
What are expressions in AngularJS ?
In this article, we will see the expressions in Angular JS, along with knowing the different methods for implementing it through the code examples.Expressions in AngularJS, are the statements that are to be evaluated, that is placed inside the double curly braces. The result of the evaluation will b
5 min read
AngularJS Expressions
In this article, we will see the Expressions in AngularJS, along with understanding their implementation through the examples. Expressions in AngularJS are used to bind application data to HTML. The expressions are resolved by AngularJS and the result is returned back to where the expression is writ
2 min read
What is Angular ?
Angular is an open-source web application framework maintained by Google and a community of developers. It is designed to build dynamic and interactive single-page applications (SPAs) efficiently. With Angular, developers can create robust, scalable, and maintainable web applications. Table of Conte
5 min read
What is Interpolation in AngularJS ?
In this article, we will know about Interpolation in AngularJS, along with understanding the basic implementation. In AngularJS, Interpolation is a way to transfer the data from a TypeScript code to an HTML template (view), i.e. it is a method by which we can put an expression in between some text a
2 min read
Expressions in Math
Expressions in math are combinations of numbers, variables, operators, and sometimes parentheses that represent a particular value. An expression is a statement involving at least two different numbers or variables and at least one operation, such as addition, subtraction, multiplication, division,
6 min read
What is pipe() function in Angular ?
Angular stands out as a liked JavaScript framework for developing web applications. In Angular, the pipe() function plays a vital role in transforming data within templates. It allows you to apply various transformations to data before displaying it in the view. In this article, we will explore more
4 min read
What are Directives in AngularJS ?
AngularJS directives are extended HTML attributes having the prefix ng-. Directives are markers on the DOM element which tell Angular JS to attach a specified behavior to that DOM element or even transform the DOM element with its children. During compilation, the HTML compiler traverses the DOM mat
7 min read
What type of algebraic expression is 4x + 5?
The concept of algebra taught us how to express an unknown value using letters such as x, y, z, etc. These letters are termed here as variables. This expression can be a combination of both variables and constants. Any value that is placed before and multiplied by a variable is termed a coefficient.
5 min read
What is Angular Material?
User Experience is one of the most important things in web development. Angular Material emerges as a powerful tool for developers, offering numerous UI components designed to elevate your Angular applications to new heights of elegance and functionality. In this article, we'll learn more about Angu
4 min read
Expressions And Equations
Expression and Equations are two important concepts of algebra in mathematics. We need to learn about expressions and equations to solve different types of easy and complex problems in both mathematics and real-life applications. expression is a combination of numbers, variables, and operators while
6 min read