` constructor(private _api: ApiRequest,
private _cookie: CookieService,
public element: ElementRef,
public renderer2: Renderer2,
private _commonService: CommonService,
private _router: Router) {
}`
`let btn3=this.element.nativeElement.querySelector('#btn3');
this.renderer2.listen(btn3,"click",()=> {
//this.renderer2.setStyle(ul, "background", "blue");
alert(22222);
})
`
html
<button type="button" id="btn3" class="tl-btn tl-btn-primary" >添加文字</button>
