當加載CustomExceptionHandler時，Angular 2注入器無法找到服務

Question

嘗試向我的CustomExceptionHandler注入服務時，Angular注入器找不到該服務。

錯誤：Uncaught Can't resolve all parameters for CustomExceptionHandler: (?).

的設置：

CustomExceptionHandler

import { ExceptionHandler } from '@angular/core'; 

import { ServiceA } from '../services/a.service'; 

export class CustomExceptionHandler extends ExceptionHandler { 

    constructor(private serviceA: ServiceA) { 
    super(null, null); 
    } 

    call(error, stackTrace = null, reason = null) { 
     //do something with the service 
    } 
} 

app.module

@NgModule({ 
    declarations: [ 
    ... 
    ], 
    imports: [ 
    ... 
    ], 
    providers: [ 
    ServiceA, 
    { provide: ExceptionHandler, useClass: CustomExceptionHandler }, 
    ], 
    bootstrap: [AppComponent], 
}) 
export class AppModule { } 

Answer 1

更新ExceptionHandler更名爲ErrorHandlerhttps://stackoverflow.com/a/35239028/217408

orgiginal

添加@Injectable()您CustomExceptionHandler類。

添加CustomExceptionHandler作爲app.module.ts你的供應商的另一個問題：

@NgModule({ 
    declarations: [ 
    ... 
    ], 
    imports: [ 
    ... 
    ], 
    providers: [ 
    ServiceA, 
    CustomExceptionHandler, 
    { provide: ExceptionHandler, useClass: CustomExceptionHandler }, 
    ], 
    bootstrap: [AppComponent], 
}) 
export class AppModule { } 

Answer 2

你需要CustomExceptionHandler及其依賴添加到providers還有：

@NgModule({ 
    declarations: [ 
    ... 
    ], 
    imports: [ 
    ... 
    ], 
    providers: [ 
    ServiceA, 
    CustomExceptionHandler, 
    { provide: ExceptionHandler, useClass: CustomExceptionHandler }, 
    ], 
    bootstrap: [AppComponent], 
}) 
export class AppModule { }