Angular 2 ngModelChange old value

This might work

(ngModelChange)="onModelChange(oldVal, $event); oldVal = $event;"

or

(ngModelChange)="onModelChange($event)"

oldValue:string;onModelChange(event) {  if(this.oldValue != event) {    ...  }  this.oldValue = event;}

Just for the future

we need to observe that [(ngModel)]="hero.name" is just a short-cut that can be de-sugared to: [ngModel]="hero.name" (ngModelChange)="hero.name = $event".

So if we de-sugar code we would end up with:

<select (ngModelChange)="onModelChange()" [ngModel]="hero.name" (ngModelChange)="hero.name = $event">

or

<[ngModel]="hero.name" (ngModelChange)="hero.name = $event" select (ngModelChange)="onModelChange()">

If you inspect the above code you will notice that we end up with 2 ngModelChange events and those need to be executed in some order.

Summing up: If you place ngModelChange before ngModel, you get the $event as the new value, but your model object still holds previous value.If you place it after ngModel, the model will already have the new value.

SOURCE

Sample stack blitz:https://stackblitz.com/edit/angular-ivy-zlhwex

Example with input field...

<div *ngFor="let value of values">{{value}}    <input [(ngModel)]="value" (focus)="old=value" (ngModelchange)="doSomething(old, value)"></div>doSomething(oldVal, newVal) {    // some code}