set invalid invalid form control in angular2

Question

Is it possible to set as invalid form control in angular2? (used form builder)

eg. i have form-> exampleFrom & field-> exampleControl

I have tried this, not succeed :

this.exampleFrom.controls['exampleControl'].invalid 

Answer 1

Try

let control = this.exampleFrom.controls['exampleControl'];
control.setErrors({backend: {someProp: "Backend message"}});
let message = control.errors['backend'].someProp;