An Angular template-driven form is a way to create forms in Angular applications using HTML templates and directives. It's a simpler approach compared to reactive forms, making it suitable for basic forms with straightforward validation requirements.
How Template-Driven Forms Work:
- HTML Templates: You define the form structure and input fields directly within your HTML template using standard HTML form elements like
<form>
,<input>
,<textarea>
, and<select>
. - Directives: Angular provides directives like
ngModel
,required
,minlength
, andmaxlength
to bind form data to component variables and implement validation rules. - Data Binding: The
ngModel
directive binds the value of an input field to a component property. Any changes made in the input field are automatically reflected in the component, and vice versa. - Validation: Angular's built-in directives and custom validation logic allow you to enforce data constraints and provide feedback to the user.
Advantages of Template-Driven Forms:
- Simplicity: Easier to learn and use for basic forms.
- Declarative: Form structure and validation are defined declaratively in the HTML template.
- Built-in Validation: Angular provides a set of built-in validation directives for common validation scenarios.
Example:
<form #myForm="ngForm">
<div>
<label for="name">Name:</label>
<input type="text" id="name" name="name" ngModel required minlength="3">
</div>
<div>
<button type="submit" [disabled]="!myForm.valid">Submit</button>
</div>
</form>
In this example, the ngModel
directive binds the name
input field to a component property, required
enforces that the field is not empty, and minlength
ensures the name has at least 3 characters. The [disabled]
attribute on the submit button prevents submission until the form is valid.
Conclusion:
Template-driven forms are a suitable choice for simple forms in Angular applications where the validation requirements are not complex. They offer a straightforward and declarative approach to form creation and validation.