What is ngModel and how is it used in Angular?
💡 Concept Name
ngModel – A directive in Angular that provides two-way data binding between the component class and the template input element.
📘 Quick Intro
ngModel is part of Angular's FormsModule and allows you to bind input fields to component properties so that changes in the UI update the model and vice versa.
🧠 Analogy / Short Story
Think of ngModel as a walkie-talkie between your HTML input and your component variable. Say something into one end (user types), and the other hears it (variable updates) instantly.
🔧 Technical Explanation
- 🔄 Enables two-way binding with the
[(ngModel)]syntax. - 📂 Requires importing
FormsModulein the Angular module. - 👨💼 Automatically reflects updates both in the component and the view.
- 🔀 Can be used to bind input, textarea, select, and other form fields.
- 📋 Part of the template-driven forms approach in Angular.
🌟 Purpose & Use Case
- ✅ Creating dynamic and user-friendly forms
- ✅ Instant field updates with real-time feedback
- ✅ Keeping component variables and UI inputs synchronized
- ✅ Building input fields with validation logic
💻 Real Code Example
// app.component.ts
export class AppComponent {
email: string = "";
}<!-- app.component.html -->
<input [(ngModel)]="email" placeholder="Enter your email" />
<p>You entered: {{ email }}</p>
❓ Interview Q&A
Q1: What is ngModel used for?
A: For creating two-way data binding between a component property and an input field.
Q2: What must be imported to use ngModel?
A: FormsModule.
Q3: Can ngModel be used on dropdowns?
A: Yes, it can be used with select elements.
Q4: Is ngModel a part of reactive forms?
A: No, it's part of template-driven forms.
Q5: What is the syntax for ngModel binding?
A: [(ngModel)]="property"
💡 Bonus Insight
For more advanced use cases like nested or dynamic forms, consider switching to ReactiveFormsModule which provides greater flexibility and control.
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