patch Value in a nested form control using angular2

Question

I need to set a value in a nested control in a FormBuiler and the model is the following:

this.addAccForm = this.fb.group({
      accid: [\'\', Validators.re         


        

Answer 1

Define a FormGroup to hold a form.
addAccForm: FormGroup

Create a form using FormBuilder.

this.addAccForm = this.fb.group({
    accid: ['', Validators.required],
    status: '',
    cyc: this.fb.array([])
})

Now create a method to patch the form values. You may pass the model as parameters to the method. Or a variable defined in the component class.

// GETER TO RETRIEVE THE CYC FORMARRAY
get cycFormArray(): FormArray {
    return this.addAccForm.get('cyc') as FormArray;
}

patchForm(model: any) {
   this.addAccForm.patchValue({
       accid: [model.accid, Validators.required],
       status: model.status,
   });

   // PASS ARRAY TO PATCH FORM ARRAY
   this.patchCyc(model.cyc);
}

// METHOD TO PATCH FORM ARRAY 
patchCyc(cycArray: any[]) {
    cycArray.forEach(item => {
        this.cycFormArray.push({
            this.fb.group({
               prop1: item.prop1,
               prop2: item.prop2,
               ...
            })
        })
    })
}

The patchCyc() method will loop through the array passed as parameter. A new FormGroup will be pushed to the cyc FormArray in each loop.