formGroup.get vs formGroup.controls in reactive form - Angular

AngularAngular Reactive-Forms

Angular Problem Overview


Is there any preferred way when selecting validation using

  • myForm.controls['name'].valid
  • myForm.get('name').valid

as both seems to be only syntactically different but achieving the same goal.

<label>Name
  <input type="text" formControlName="name">
</label>
<div class="alert" *ngIf="!myForm.controls['name'].valid && myForm.controls['name'].touched">
  {{ titleAlert }}
</div>

Same as

<div class="alert" *ngIf="!myForm.get('name').valid && myForm.get('name').touched">
  {{ titleAlert }}
</div>

From what I checked in the code, get has this code:

AbstractControl.prototype.get = function (path) { return _find(this, path, '.'); };

I have just started Angular, so an expert opinion would be appreciated.

Angular Solutions


Solution 1 - Angular

Just like what you have found, FormGroup.get is designed to access target formcontrol by it's path. And it's more often used for complicated(multi layer embed) situation, which makes it easy to get the target control from multi layer embed form and also makes code clear and easily to understand.

Take below as a example, you can simply access the first element of the embed FormArray by this.form.get('test.0') instead of this.form.controls.test.controls[0]:

this.form = this.formBuilder.group(
  {
    test: this.formBuilder.array(
      [
        ['form control 1 in form array'],
        ['form control 1 in form array'],
        ...
      ]
    )
  }
);

Solution 2 - Angular

This question is related to: https://stackoverflow.com/questions/62033196/will-using-angular-reactive-forms-get-method-in-template-cause-unnecessary-me.

In templates I prefer using myForm.controls.name to avoid the myForm.get('name') function call. If the field selector is very complex, then I would store the field in a component attribute so in the template its access is instant.

In controllers it shouldn't matter too much using one or another.

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionSamuelView Question on Stackoverflow
Solution 1 - AngularPengyyView Answer on Stackoverflow
Solution 2 - AngularJosé Antonio PostigoView Answer on Stackoverflow