3.1 KiB
@cheatsheetSection
Class field decorators for directives and components
@cheatsheetIndex 8
@description
{@target ts}import { Input, ... } from '@angular/core';{@endtarget}
{@target js}Available from the ng.core namespace{@endtarget}
@cheatsheetItem
syntax(ts):
@Input() myProperty;|@Input()
syntax(js):
ng.core.Input(myProperty, myComponent);|ng.core.Input(|);
description:
Declares an input property that you can update via property binding (example:
<my-cmp [myProperty]="someExpression">).
@cheatsheetItem
syntax(ts):
@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 that you can subscribe to with an event binding (example: <my-cmp (myEvent)="doSomething()">).
@cheatsheetItem
syntax(ts):
@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 (here, the CSS class valid) to a directive/component property (isValid).
@cheatsheetItem
syntax(ts):
@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 (click) with a directive/component method (onClick), optionally passing an argument ($event).
@cheatsheetItem
syntax(ts):
@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 a property (myChildComponent) of the class.
@cheatsheetItem
syntax(ts):
@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 a property (myChildComponents) of the class.
@cheatsheetItem
syntax(ts):
@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 a property (myChildComponent) of the class. Not available for directives.
@cheatsheetItem
syntax(ts):
@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 a property (myChildComponents) of the class. Not available for directives.