angular’s ng-init alternative in Angular 2

You can use a directive

@Directive({
  selector: 'ngInit',
  exportAs: 'ngInit'
}) 
export class NgInit {
  @Input() values: any = {};

  @Input() ngInit;
  ngOnInit() {
    if(this.ngInit) { this.ngInit(); }
  }  
}

you can use it to pass a function to be called like

<div [ngInit]="doSomething"

or to make values available

<div ngInit [values]="{a: 'a', b: 'b'}" #ngInit="ngInit">
  <button (click)="clickHandler(ngInit.values.a)">click me</button>
</div>

• ngInit addes the directive
• [values]="{a: 'a', b: 'b'}" sets some initial values
• #ngInit="ngInit" creates a reference for later use
• ngInit.values.a reads the a value from the created reference.

See also Converting Angular 1 to Angular 2 ngInit function