Update a Reactive Form

The point of this step is to introduce you with the solutions to update the value of a reactive form. A reactive form is a set of classes you use, in our situation, initialized as so:

form = new FormGroup({
  title: new FormControl(""),
  description: new FormControl(""),
});

To update it, you can’t juste set it a value directly, like form = {title: "New Title", description: "New Description"} because it’s not a regular object.

The Reactive Forms API provides you with two methods to update the value of a reactive form:

• setValue() sets all form control values at once and requires you to provide values for every form control - if you miss any, it throws an error.

• patchValue() updates some or all form controls and ignores missing properties - it only updates the controls that match.

Note

Use setValue() to completely replace all form values, use patchValue() for partial updates.

Instructions

1. Update the TaskForm class:

   task.form.ts

   
   preFillForm() {
       this.form.setValue({
         title: 'Generated Task',
         description: 'Generated Description',
       });
   }

Note

With setValue() if you miss any, it throws an error. Use it when you want to completely replace all form values.