How to pass data from parent to child component in Angular 4

Question

When I try to pass data from parent to child component. I\'m getting undefined message in the console. Data is in the form of array.

parent.component.html

Answer 1

You can't do the assignment in the constructor as the value has not yet been populated, it should be done in ngOnInit just like your check of the value.

@Input() data;
question = [];

constructor() {
}

ngOnInit() {
  this.question = this.data;
  console.log(this.question);
}