指令Angular 2上的停止按钮单击事件

Question

我用angular 2和PrimeNG构建了我的应用程序。我尝试使用按钮单击指令来检查用户权限。问题是；如果没有权限，请不要继续执行按钮单击操作。但是stopPropagation不会停止click事件。如果checkAuth（）返回false，如何停止进程？

块引用

@Directive({
    selector: '[checkAuthOnClick]'
})

export class CheckAuthorizationOnClickDirective {

    user: Observable<User>;
    @Input() allowedClaim: any;
    observer: MutationObserver;

    constructor(private element: ElementRef, private store: Store<fromRoot.State>) {
        this.element = element.nativeElement;
    }

    @Output()
    stop: EventEmitter<Event> = new EventEmitter;

    @HostListener('click', ['$event, $event.target'])
    onClick(event, targetElement) {  
        if (!this.checkAuth()) {
            event.stopPropagation();
            event.preventDefault();
            event.cancelBuble = true;
            event.stopImmediatePropagation();

            this.stop.emit(event);
        }
    }   

    private checkAuth(): boolean {
        this.user = this.store.select(fromRoot.currentUser);
        if (this.user != undefined && this.allowedClaim != undefined) {
            var hasClaim = false;
            var description;
            this.user.subscribe(x => {
                if (Array.isArray(this.allowedClaim)) { //Gelen/Giden Faturalar? görüntüleme yetkileri tümü ve kendisine ait o.? birden çok oldu?u için app.routes'ta array olarak tan?mland?. 
                    for (let i = 0; i < this.allowedClaim.length; i++) {
                        hasClaim = x.hasClaim(this.allowedClaim[i])
                        if (hasClaim)
                            break;
                    }

                    description = this.allowedClaim[0].Description;
                }
                else {
                    hasClaim = x.hasClaim(this.allowedClaim);
                    description = this.allowedClaim.Description;
                }
            });

            if (hasClaim == false) {
                var message = "Bu i?lem için yetkiniz yoktur.";
                if (description != undefined) {
                    message = description + ' yetkiniz yoktur.'
                }

                this.store.dispatch(new ui.ToastMessagePushAction({ severity: 'warning', summary: message, detail: '' }));
            }
        }

        return hasClaim;
    }

}

像这样在html上的指令用法；

<button type="button" pButton icon="fa fa-file-code-o" (click)="createForm()" checkAuthOnClick [allowedClaim]="systemDefinedClaims?.CreateInvoiceDesign"></button>

Answer 1

通过(click)和绑定事件HostBinding仅意味着将两个独立的事件绑定到目标元素，它们将被同时调用，并且不会互相影响，这意味着停止其中的任何一个都不会停止另一个事件。

您需要在指令的点击事件绑定中通过手动调用click事件（当前通过绑定(click)）HostBinding。

// transfer click event into directive
@Input('clickEvent') clickEvent;


@HostListener('click', ['$event, $event.target'])
onClick(event, targetElement) {  
    if (!this.checkAuth()) {
        event.stopPropagation();
        event.preventDefault();
        event.cancelBuble = true;
        event.stopImmediatePropagation();

        this.stop.emit(event);
    } else {
        this.clickEvent();
    }
}    

请参阅示例演示。