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

you can use this to clear validation from reactive form

this.form.controls['title'].clearValidators(); this.form.controls['title'].updateValueAndValidity();

you can use this to add validation in reactive form

this.form.controls['title'].setValidators([Validators.required]); this.form.controls['title'].updateValueAndValidity();