HostListener
Decorator that declares a DOM event to listen for, and provides a handler method to run when that event occurs.
| 选项 | 说明 |
|---|---|
eventName | 要监听的事件。 The CSS event to listen for. |
args | 当该事件发生时传给处理器方法的一组参数。 A set of arguments to pass to the handler method when the event occurs. |
使用说明
下面的例子声明了一个指令，它会为按钮附加一个 click 监听器，并统计点击次数。
The following example declares a directive that attaches a click listener to a button and counts clicks.
- @Directive({selector: 'button[counting]'})
- class CountClicks {
- numberOfClicks = 0;
-
- @HostListener('click', ['$event.target'])
- onClick(btn) {
- console.log('button', btn, 'number of clicks:', this.numberOfClicks++);
- }
- }
-
- @Component({
- selector: 'app',
- template: '<button counting>Increment</button>',
- })
- class App {}
