Angular 4 remove required validator conditionally

Question

In Angular 4 app I have a form model like this:

this.form = this._fb.group({
    title: [\'\', [Validators.required, Validators.minLength(3), Validators.maxLengt         


        

Answer 1

I had the same problem with saving entry as draft and prepared the following solution:

@Component({
    // ...
})
export class FormComponent{
    form: FormGroup;

    constructor(private fb: FormBuilder){
        this.form = this.fb.group({
            name: ['', Validators.required, Validators.maxLength(20)],
            description: ['', Validators.required, Validators.maxLength(200)],
            address: this.fb.group({
                line1: ['', Validators.required, Validators.maxLength(100)],
                line2: ['', Validators.maxLength(100)]
            })
        });
    }    

    validateDraft(formElement: FormGroup | FormArray | FormControl): boolean {
        let result = true;

        Object.keys(formElement.controls).forEach(field => {
            const control = formElement.get(field);

            if(control instanceof FormControl) {
                control.markAsTouched({ onlySelf: true });

                if(control.errors && control.errors['required']) {
                    control.markAsUntouched({ onlySelf: true });
                }
                else if(control.invalid) {
                    result = false;
                }
            } else if (control instanceof FormArray) {
                if (!this.validateDraft(control)) {
                    result = false;
                } 
            }else if (control instanceof FormGroup) {
                if (!this.validateDraft(control)) {
                    result = false;
                }   
            }
        });
    }

    saveDraft(){
        if(this.validateDraft(this.form)){
            //save draft - ignore required errors
        }
    }

    save(){
        if(this.form.valid){
            //save
        }
    }
}