角度延迟加载模块错误 - 'RouterModule.forRoot() 调用了两次'

Question

我正在我的 Angular 6 应用程序中实现延迟加载的功能模块，并已成功为“发票”功能配置了一个，但我在为延迟加载的“费用”和“联系人”实现路由时遇到问题功能模块，其设置方式与第一个相同。

每个模块都被导入到 AppModule 中，它们还使用了一个 SharedModule，我已经将它导入到 AppModule 和每个功能模块中。

当使用“费用”或“联系人”模块路由到任何页面时，我在控制台中收到以下错误：

ERROR 错误：未捕获（承诺中）：错误：RouterModule.forRoot() 调用了两次。延迟加载的模块应该使用 RouterModule.forChild() 代替。 错误：RouterModule.forRoot() 调用了两次。延迟加载的模块应该使用 RouterModule.forChild() 代替。 在provideForRootGuard (vendor.js:106249)

我 am 将 .forChild(routes) 用于功能模块，但我能想到的唯一可能导致此问题的是过程中某处的纠结导入。根据之前关于其他人遇到此问题的问题，我检查了 AppModule 是否已导入任何其他模块，因此导致 forRoot() 被调用两次，但事实并非如此。

在provideForRootGuard 出现的错误说明与它有关，我认为这可能与将CanActivateRootGuard 导入每个模块有关，但删除它也不能解决问题。

AppRoutingModule：

import { NgModule } from '@angular/core';
import { RouterModule, Routes, RouterLinkActive } from '@angular/router';
import { CanActivateRouteGuard } from './can-activate-route.guard';

// COMPONENTS
  // Dashboard
  import { DashboardComponent } from './dashboard/dashboard.component';
  // Login
  import { LoginComponent } from './login/login.component';
  // Register
  import { RegisterComponent } from './register/register.component';
  // Notifications
  import { NotificationsComponent } from './notifications/notifications.component';
  // Bank
  import { BankComponent } from './bank/bank.component';
  // Documents
  import { DocumentsComponent } from './documents/documents.component';

const routes: Routes = [
  {
    path: '',
    redirectTo: 'login',
    pathMatch: 'full'
  },
  {
    path: 'dashboard',
    component: DashboardComponent,
    canActivate: [CanActivateRouteGuard]
  },

  // Login/Register
  {
    path: 'login',
    component: LoginComponent
  },
  {
    path: 'register',
    component: RegisterComponent
  },

  // Notifications
  {
    path: 'notifications',
    component: NotificationsComponent,
    canActivate: [CanActivateRouteGuard]
  },
  {
    path: 'notifications/:id',
    component: NotificationsComponent,
    canActivate: [CanActivateRouteGuard]
  },

  // Bank
  {
    path: 'bank',
    component: BankComponent,
    canActivate: [CanActivateRouteGuard]
  },

  // Contacts
  {
    path: 'contacts',
    loadChildren: './contacts/contacts.module#ContactsModule'
  },

  // Expenses
  {
    path: 'expenses',
    loadChildren: './expenses/expenses.module#ExpensesModule'
  },

  // Invoices
  {
    path: 'invoices',
    loadChildren: './invoices/invoices.module#InvoicesModule'
  },

  // Documents
  {
    path: 'documents',
    component: DocumentsComponent,
    canActivate: [CanActivateRouteGuard]
  }
]

@NgModule ({

  imports: [
    RouterModule.forRoot(routes)
  ],

  exports: [
    RouterModule
  ]

})

AppModule

// ANGULAR CORE
import { BrowserModule } from '@angular/platform-browser';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { NgModule } from '@angular/core';

// FEATURE MODULES
import { ContactsModule } from '@app/contacts/contacts.module';
import { ExpensesModule } from '@app/expenses/expenses.module';
import { InvoicesModule } from '@app/invoices/invoices.module';
import { BankModule } from '@app/bank/bank.module';
import { DocumentsModule } from '@app/documents/documents.module';

// MATERIAL MODULE
import { MaterialModule } from '@app/material.module';

// SHARED MODULE
import { SharedModule } from '@app/shared.module';

// COMPONENTS
import { AppComponent } from './app.component';
import { DashboardComponent } from './dashboard/dashboard.component'

// Account
import { LoginComponent } from './login/login.component'
import { RegisterComponent } from './register/register.component'
import { VerifyEmailDialogComponent } from './register/dialogs/verify-email-dialog/verify-email-dialog.component';

// Notifications
import { NotificationsComponent } from './notifications/notifications.component';

@NgModule({

  declarations: [
    AppComponent,

    // COMPONENTS
        // Dashboard
        DashboardComponent,
        // Login
        LoginComponent,
        // Register
        RegisterComponent,
            // Dialogs
            VerifyEmailDialogComponent,
        // Notifications
        NotificationsComponent
  ],

  imports: [
    // ANGULAR CORE
    BrowserModule,
    BrowserAnimationsModule,

    // FEATURE MODULES
    InvoicesModule,
    ContactsModule,
    ExpensesModule,
    BankModule,
    DocumentsModule,

    // MATERIAL MODULE
    MaterialModule,

    // SHARED MODULE
    SharedModule
  ],

  entryComponents: [
    // DIALOGS  
        // Register
        VerifyEmailDialogComponent
  ],

  providers: [

  ],

  bootstrap: [AppComponent]
})

export class AppModule { }

费用路由模块

import { NgModule } from '@angular/core';
import { RouterModule, Routes, RouterLinkActive } from '@angular/router';
// import { CanActivateRouteGuard } from '@app/can-activate-route.guard';

// COMPONENTS
import { NewExpenseComponent } from './new-expense/new-expense.component';
import { ExpenseListComponent } from './expense-list/expense-list.component';
import { ViewExpenseComponent } from './view-expense/view-expense.component';

const routes: Routes = [
  {
    path: 'expenses/new',
    component: NewExpenseComponent,
    // canActivate: [CanActivateRouteGuard]
  },
  {
    path: 'expenses/all',
    component: ExpenseListComponent,
    // canActivate: [CanActivateRouteGuard]
  },
  {
    path: 'expenses/:id',
    component: ViewExpenseComponent,
    // canActivate: [CanActivateRouteGuard]
  },
]

@NgModule({

  imports: [
    RouterModule.forChild(routes)
  ],

  exports: [
    RouterModule
  ]

})

export class ExpensesRoutingModule {

}

费用模块

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';

import { ExpensesRoutingModule } from './expenses-routing.module';

// SHARED/MATERIAL MODULES
import { SharedModule } from '@app/shared.module';
import { MaterialModule } from '@app/material.module';

// COMPONENTS
    // New Expense
    import { NewExpenseComponent } from './new-expense/new-expense.component';
    // Expense List
    import { ExpenseListComponent } from './expense-list/expense-list.component';
    // View Expense
    import { ViewExpenseComponent } from './view-expense/view-expense.component';
    // Dialogs
    import { DeleteExpenseDialogComponent } from './view-expense/dialogs/delete-expense-dialog/delete-expense-dialog.component';

@NgModule({

  imports: [
    CommonModule,
    ExpensesRoutingModule,
    SharedModule,
    MaterialModule
  ],

  declarations: [
    // COMPONENTS
        // New Expense
        NewExpenseComponent,
        // Expense List
        ExpenseListComponent,
        // View Expense
        ViewExpenseComponent,
            // Dialogs
            DeleteExpenseDialogComponent
  ],

  entryComponents: [
    // DIALOGS
        // View Expense
        DeleteExpenseDialogComponent
  ]

})

export class ExpensesModule {

}

SharedModule 路由导入

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';

// ROUTING
import { AppRoutingModule } from './app-routing.module';
import { RouterLinkActive, CanActivate } from '@angular/router';
import { CanActivateRouteGuard } from './can-activate-route.guard';

...

Answer 1

修复

设法通过将 AppRoutingModule 从 SharedModule 中移除并改为 AppModule 来解决此问题。现在所有路线都运行良好。

Answer 2

您将 AppRoutingModule 包含在 SharedModule 中。
然后从功能模块（如 ExpensesModule）中加载此共享模块
所以你实际上是在加载它两次。
要解决此问题，您必须将其从共享模块中取出。如果您想保留任何共享路由，只需将其分隔为不同的文件，将核心路由保留在共享模块之外，并将其与 forRoot 一起包含在您的主模块中。