The Angular uses the ngModel directive to achieve the two-way binding on HTML Form elements. It binds to a form element like input , select , selectarea . etc. Internally It uses the ngModel in property, binding to bind to the value property and ngModelChange which binds to the input event.
OnPush change detection: this works by detecting if some new data has been explicitly pushed into the component, either via a component input or an Observable subscribed to using the async pipe.
Update:
Separate the event and property bindings:
<select [ngModel]="selectedItem" (ngModelChange)="onChange($event)">
onChange(newValue) {
console.log(newValue);
this.selectedItem = newValue; // don't forget to update the model here
// ... do other stuff here ...
}
You could also use
<select [(ngModel)]="selectedItem" (ngModelChange)="onChange($event)">
and then you wouldn't have to update the model in the event handler, but I believe this causes two events to fire, so it is probably less efficient.
Old answer, before they fixed a bug in beta.1:
Create a local template variable and attach a (change)
event:
<select [(ngModel)]="selectedItem" #item (change)="onChange(item.value)">
plunker
See also How can I get new selection in "select" in Angular 2?
I have stumbled across this question and I will submit my answer that I used and worked pretty well. I had a search box that filtered and array of objects and on my search box I used the (ngModelChange)="onChange($event)"
in my .html
<input type="text" [(ngModel)]="searchText" (ngModelChange)="reSearch(newValue)" placeholder="Search">
then in my component.ts
reSearch(newValue: string) {
//this.searchText would equal the new value
//handle my filtering with the new value
}
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