在绑定导航器之前,可以使用canDeactivate
守卫来检查是否可以删除关联。下面是一个基本的代码示例:
import { Injectable } from '@angular/core';
import { CanDeactivate } from '@angular/router';
import { Observable } from 'rxjs';
// 创建一个可取消绑定的接口
export interface CanComponentDeactivate {
canDeactivate: () => Observable | Promise | boolean;
}
@Injectable()
export class CanDeactivateGuard implements CanDeactivate {
// 实现CanDeactivate守卫
canDeactivate(component: CanComponentDeactivate): Observable | Promise | boolean {
return component.canDeactivate ? component.canDeactivate() : true;
}
}
然后,在你的组件中实现CanComponentDeactivate
接口,并在canDeactivate
方法中进行关联检查。下面是一个示例:
import { Component } from '@angular/core';
import { CanComponentDeactivate } from './can-deactivate.guard';
import { Observable } from 'rxjs';
@Component({
selector: 'app-my-component',
template: `
My Component
`
})
export class MyComponent implements CanComponentDeactivate {
canDeactivate(): Observable | Promise | boolean {
// 在这里进行关联检查,返回一个Observable、Promise或布尔值
// 如果关联存在,返回true,否则返回false或一个可以确认用户操作的可观察对象
return confirm('Are you sure you want to delete?');
}
onDelete() {
// 删除操作
}
}
最后,将CanDeactivateGuard
添加到你的路由配置中,以在删除之前检查关联。例如:
import { NgModule } from '@angular/core';
import { RouterModule, Routes } from '@angular/router';
import { MyComponent } from './my-component';
import { CanDeactivateGuard } from './can-deactivate.guard';
const routes: Routes = [
{
path: 'my-component',
component: MyComponent,
canDeactivate: [CanDeactivateGuard] // 将CanDeactivateGuard添加到canDeactivate属性中
}
];
@NgModule({
imports: [RouterModule.forRoot(routes)],
exports: [RouterModule]
})
export class AppRoutingModule { }
这样,在用户尝试导航离开MyComponent
组件之前,会调用CanDeactivateGuard
来执行关联检查。如果检查通过,用户将被允许导航到其他组件,否则导航将被阻止。