How can the ngIf condition be shortened if only one property in the condition changes?

Question

JavaScript

There is such a condition, but it is very large and only one property is always repeated: firstName

<span *ngIf="registrationForm.controls.firstName.errors && registrationForm.controls.firstName.errors.required && registrationForm.controls.firstName.touched" class="clr-subtext">This field is required</span>

This piece is similar to the piece above, but with a different property: email

<span *ngIf="registrationForm.controls.email.errors && registrationForm.controls.email.errors.required && registrationForm.controls.email.touched" class="clr-subtext">This field is required</span>

Answer 1

isFieldRequired(field: string): boolean {
    const control = this.registrationForm.controls[field];
    return control.errors && control.errors.required && control.touched;
}