Input change event in Angular 17

Input change event in Angular 17

Handling input change events is a fundamental aspect of building interactive web applications with Angular 17. It allows you to respond to user actions and update the UI accordingly. In this step-by-step tutorial, you'll learn how to handle input change events in Angular 17.

Prerequisites:

  • Basic understanding of Angular fundamentals
  • Familiarity with HTML
  • Code editor (e.g., Visual Studio Code)

Step 1: Create an Angular Project

  1. Initialize a new Angular project using the CLI:
ng new input-change-event-demo
  1. Navigate into the project directory:
cd input-change-event-demo

Step 2: Implement Input Change Event Handling

  1. Open the app.component.html file.
  2. Add an input element with the (change) event binding. The change event fires when the input value changes.
<input type="text" (change)="onChange($event)" />

Step 3: Define the Event Handler Method

  1. Open the app.component.ts file.
  2. Import the Event object from the @angular/core package.
import { Component, Event } from '@angular/core';
  1. Define the onChange() method to handle the input change event.
onChange(event: Event) {
  // Get the new input value
  const newValue = (event.target as HTMLInputElement).value;
  // Perform actions based on the new value
  console.log('Input value changed:', newValue);
}

Step 4: Run the Angular Application

  1. Start the Angular development server:
ng serve
  1. Open the application in your web browser:
http://localhost:4200
  1. Enter text in the input field and observe the console output. The onChange() method will be triggered, and the new input value will be logged to the console.