How to set value in array form with Angular

Question

I want to set value in array like this:

this.form.controls[name].setValue(\'name\')

but I am working w

Answer 1

Here is what I have done to set value manually in formArray's specific form control and worked for me. I have formArray named as bundleDetails.

   this.formBuilderObj['bundleDetails'] = 
   this.formBuilder.array([this.createBundleItem()]);

    createBundleItem(): FormGroup {
    return this.formBuilder.group({
     bsku: ['', Validators.required],
     bqty: ['', Validators.required],
     bprice: ['', Validators.required]
    });
   }

Method to set bsku control's value (where index is [formGroupName]="i" passed from html file).

   setSku(sku: string, index: number) {
   const faControl = 
   (<FormArray>this.pmForm.controls['bundleDetails']).at(index);
   faControl['controls'].bsku.setValue(sku);
  }

Hope this helps. Happy coding.

Answer 2

If you're getting the error "ERROR Error: Cannot find control with path: 'addresses -> 0 -> addressType'" or something similar, it's most likely cause you're passing the values in but your html template is expecting values along with a control name.

To resolve this, iterate over each item in your array, and create a new form group instance for each value - based on what your view is expecting - then push to a new array variable, which we then set in our form.

See code below:

var tagsArray = [];
this.product.tags.forEach(product => tagsArray.push(this.fb.group({tag: [product.tag, [Validators.required]]})));
this.productForm.setControl('tags', this.fb.array(tagsArray || []));

Referenced in view like so:

<div class="tag" *ngFor="let t of tags.controls; let i = index" [formGroupName]="i" class="mb-2">
      <input type="text" formControlName="tag" placeholder="Tag name" class="primary_input">
       <button mat-icon-button (click)="deleteTag(i)">
           <mat-icon>clear</mat-icon>
       </button>
 </div>

This lets you load previous results while enabling the ability to add more values and validate user input.

Hope this helps.

Answer 3

For arrays, you need to use setControl. Something like this:

    this.productForm = this.fb.group({
        productName: ['', [Validators.required,
                           Validators.minLength(3),
                           Validators.maxLength(50)]],
        productCode: ['', Validators.required],
        starRating: ['', NumberValidators.range(1, 5)],
        tags: this.fb.array([]),
        description: ''
    });

    ...

    // Update the data on the form
    this.productForm.patchValue({
        productName: this.product.productName,
        productCode: this.product.productCode,
        starRating: this.product.starRating,
        description: this.product.description
    });
    this.productForm.setControl('tags', this.fb.array(this.product.tags || []));