问题描述: 在使用Angular 5时,缓存服务与路由链接之间无法正常工作。
解决方法:
canActivate
守卫来控制是否启用缓存。import { Injectable } from '@angular/core';
import { CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot, UrlTree } from '@angular/router';
import { Observable } from 'rxjs';
import { CacheService } from './cache.service';
@Injectable({
providedIn: 'root'
})
export class CacheGuard implements CanActivate {
constructor(private cacheService: CacheService) { }
canActivate(
next: ActivatedRouteSnapshot,
state: RouterStateSnapshot): Observable | Promise | boolean | UrlTree {
// 根据需要的缓存策略来判断是否启用缓存
if (this.cacheService.shouldCache()) {
return true;
} else {
return false;
}
}
}
import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { CacheGuard } from './cache.guard';
import { HomeComponent } from './home/home.component';
const routes: Routes = [
{
path: 'home',
component: HomeComponent,
canActivate: [CacheGuard] // 启用缓存
},
// 其他路由配置...
];
@NgModule({
imports: [RouterModule.forRoot(routes)],
exports: [RouterModule]
})
export class AppRoutingModule { }
localStorage
或sessionStorage
来存储缓存数据。import { Injectable } from '@angular/core';
@Injectable({
providedIn: 'root'
})
export class CacheService {
private cacheKey = 'myCacheKey';
constructor() { }
shouldCache(): boolean {
// 根据具体的逻辑来判断是否应该启用缓存
const cachedData = localStorage.getItem(this.cacheKey);
if (cachedData) {
return true;
} else {
return false;
}
}
getFromCache(): any {
// 从缓存中获取数据
return JSON.parse(localStorage.getItem(this.cacheKey));
}
setToCache(data: any): void {
// 将数据保存到缓存中
localStorage.setItem(this.cacheKey, JSON.stringify(data));
}
}
import { Component, OnInit } from '@angular/core';
import { CacheService } from '../cache.service';
@Component({
selector: 'app-home',
templateUrl: './home.component.html',
styleUrls: ['./home.component.css']
})
export class HomeComponent implements OnInit {
cachedData: any;
constructor(private cacheService: CacheService) { }
ngOnInit(): void {
// 从缓存中获取数据
this.cachedData = this.cacheService.getFromCache();
}
updateCache(): void {
// 更新缓存数据
const newData = 'New Data';
this.cacheService.setToCache(newData);
}
}
通过上述步骤,可以在Angular 5中实现缓存服务与路由链接的正常工作。请根据实际需求调整代码。