What is the proper way to initialize a property with an @Input decorator without compromising strict typing?
The code snippet below is triggering a warning:
@Input()
bar: FormGroup = new FormGroup();
What is the proper way to initialize a property with an @Input decorator without compromising strict typing?
The code snippet below is triggering a warning:
@Input()
bar: FormGroup = new FormGroup();
Creating a decorator in Typescript that guarantees field initialization is not possible. The best approach is to use a definite assignment modifier for the field:
@Input
bar!: FormControl;
By applying this modification, TypeScript will no longer enforce strict null checks for this specific field. More information about this technique can be found here
It is important to add an exclamation mark after props, for example bar!: FormControl.
Check out this related problem
If you want to make the attribute optional, simply add a question mark after it.
@Input
bar?: FormControl;
Furthermore, you can specify that the input is required in the parent component's selector:
selector: 'app-name[bar]'
This ensures that the component is only selected if the bar input is provided.
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