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@cheatsheetSection Class field decorators for directives and components @cheatsheetIndex 7 @description {@target ts}import {Input, ...} from '@angular/core';{@endtarget} {@target js}Available from the ng.core namespace{@endtarget} {@target dart}import 'package:angular2/core.dart';{@endtarget}

@cheatsheetItem syntax(ts dart): @Input() myProperty;|@Input() syntax(js): ng.core.Input(myProperty, myComponent);|ng.core.Input(|); description: Declares an input property that we can update via property binding (e.g. <my-cmp [myProperty]="someExpression">).

@cheatsheetItem syntax(ts dart): @Output() myEvent = new EventEmitter();|@Output() syntax(js): myEvent = new ng.core.EventEmitter(); ng.core.Output(myEvent, myComponent);|ng.core.Output(|); description: Declares an output property that fires events to which we can subscribe with an event binding (e.g. <my-cmp (myEvent)="doSomething()">).

@cheatsheetItem syntax(ts dart): @HostBinding('[class.valid]') isValid;|@HostBinding('[class.valid]') syntax(js): ng.core.HostBinding('[class.valid]', 'isValid', myComponent);|ng.core.HostBinding('[class.valid]', 'isValid'|); description: Binds a host element property (e.g. CSS class valid) to directive/component property (e.g. isValid).

@cheatsheetItem syntax(ts dart): @HostListener('click', ['$event']) onClick(e) {...}|@HostListener('click', ['$event']) syntax(js): ng.core.HostListener('click', ['$event'], onClick(e) {...}, myComponent);|ng.core.HostListener('click', ['$event'], onClick(e)|); description: Subscribes to a host element event (e.g. click) with a directive/component method (e.g. onClick), optionally passing an argument ($event).

@cheatsheetItem syntax(ts dart): @ContentChild(myPredicate) myChildComponent;|@ContentChild(myPredicate) syntax(js): ng.core.ContentChild(myPredicate, 'myChildComponent', myComponent);|ng.core.ContentChild(myPredicate,|); description: Binds the first result of the component content query (myPredicate) to the myChildComponent property of the class.

@cheatsheetItem syntax(ts dart): @ContentChildren(myPredicate) myChildComponents;|@ContentChildren(myPredicate) syntax(js): ng.core.ContentChildren(myPredicate, 'myChildComponents', myComponent);|ng.core.ContentChildren(myPredicate,|); description: Binds the results of the component content query (myPredicate) to the myChildComponents property of the class.

@cheatsheetItem syntax(ts dart): @ViewChild(myPredicate) myChildComponent;|@ViewChild(myPredicate) syntax(js): ng.core.ViewChild(myPredicate, 'myChildComponent', myComponent);|ng.core.ViewChild(myPredicate,|); description: Binds the first result of the component view query (myPredicate) to the myChildComponent property of the class. Not available for directives.

@cheatsheetItem syntax(ts dart): @ViewChildren(myPredicate) myChildComponents;|@ViewChildren(myPredicate) syntax(js): ng.core.ViewChildren(myPredicate, 'myChildComponents', myComponent);|ng.core.ViewChildren(myPredicate,|); description: Binds the results of the component view query (myPredicate) to the myChildComponents property of the class. Not available for directives.