错误：t没有提供者

Question

我正在尝试通过 ng build --prod 将我的角度代码编译到生产模式，并且它已成功但在浏览器中我收到错误：

ERROR p {__zone_symbol__error: Error: Uncaught (in promise): Error: NullInjectorError: No provider for t!

错误：NullInjectorError：...，...}

当我只运行 ng build 时，html工作正常。

我尝试过在git hub上提到的几个链接：

https://github.com/angular/angular/issues/19219 https://github.com/angular/angular-cli/issues/6851

没有多大帮助。

附加我的Package.json文件内容：

{
  "name": "xxx",
  "version": "0.0.0",
  "license": "MIT",
  "angular-cli": {},
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "test": "ng test",
    "pree2e": "webdriver-manager update --standalone false --gecko false",
    "e2e": "protractor",
    "build": "ng build && node server.js",
    "dev": "ng build -w & nodemon server.js --watch dist --watch server",
    "production": "ng build --prod & node server.js dist server "
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "~5.0.0",
    "@angular/common": "~5.0.0",
    "@angular/compiler": "~5.0.0",
    "@angular/compiler-cli": "~5.0.0",
    "@angular/core": "~5.0.0",
    "@angular/forms": "~5.0.0",
    "@angular/http": "~5.0.0",
    "@angular/platform-browser": "~5.0.0",
    "@angular/platform-browser-dynamic": "~5.0.0",
    "@angular/router": "~5.0.0",
    "@jaspero/ng2-alerts": "0.0.7",
    "axios": "^0.17.0",
    "body-parser": "^1.18.2",
    "cookie-parser": "^1.4.3",
    "core-js": "^2.4.1",
    "ethereumjs-tx": "^1.3.3",
    "express": "^4.16.2",
    "express-session": "^1.15.6",
    "mongoose": "^4.12.6",
    "rxjs": "^5.0.1",
    "ts-helpers": "^1.1.1",
    "web3": "^1.0.0-beta.24",
    "web3-provider-engine": "^13.3.3",
    "zone.js": "^0.7.2"
  },
  "devDependencies": {
    "@angular/cli": "^1.5.0",
    "@angular/compiler-cli": "1.5.0",
    "@types/jasmine": "2.5.38",
    "@types/node": "^6.0.42",
    "codelyzer": "~2.0.0-beta.1",
    "jasmine-core": "2.5.2",
    "jasmine-spec-reporter": "2.5.0",
    "karma": "1.2.0",
    "karma-chrome-launcher": "^2.0.0",
    "karma-cli": "^1.0.1",
    "karma-jasmine": "^1.0.2",
    "karma-remap-istanbul": "^0.2.1",
    "protractor": "~4.0.13",
    "ts-node": "1.2.1",
    "tslint": "^4.3.0",
    "typescript": "2.4.2"
  }
}

也是app.module.ts

import {BrowserModule} from '@angular/platform-browser';
import {NgModule} from '@angular/core';
import {FormsModule} from '@angular/forms';
import {HttpClientModule} from '@angular/common/http';
import {BrowserAnimationsModule} from '@angular/platform-browser/animations';
import {JasperoAlertsModule} from '@jaspero/ng2-alerts';
// Imports commented out for brevity
import {RouterModule} from '@angular/router';
// Components
import {AppComponent} from './app.component';
import {LoginComponent} from './component/login/login.component';
import {DashboardComponent} from './component/dashboard/dashboard.component';
// Services
import {RecordsService} from './services/records.service';
import {AccountService} from './services/account.service';
import {AuthenticateService} from './services/authenticate.service';
import {FooterComponent} from './component/footer/footer.component';
import {HeaderComponent} from './component/header/header.component';


// Define the routes
const ROUTES = [
  {
    path: '',
    redirectTo: 'login',
    pathMatch: 'full'
  },
  {
    path: 'login',
    component: LoginComponent
  },
  {
    path: 'dashboard',
    component: DashboardComponent
  }
];

@NgModule({
  declarations: [
    AppComponent,
    HeaderComponent,
    FooterComponent,
    LoginComponent,
    DashboardComponent
  ],
  imports: [
    BrowserModule,
    HttpClientModule,
    BrowserAnimationsModule,
    FormsModule,
    JasperoAlertsModule,
    RouterModule.forRoot(ROUTES) // Add routes to the app
  ],
  providers: [
    RecordsService,
    AccountService,
    AuthenticateService
  ],
  bootstrap: [AppComponent]
})
export class AppModule {
}

Answer 1

运行以下命令，然后首先查找缺少的服务依赖项。 在本地修复它，Prod构建将自动运行。

ng serve --prod --optimization=false

Answer 2

您正在尝试使用未在AppModule providers中列出的服务。将服务添加到提供者列表以使其工作。

Answer 3

通过编辑文件来禁用terser插件：

node_modules/@angular-devkit/build-angular/src/angular-cli-files/models/webpack-configs/common.js

并注释掉：

extraMinimizers.push(new TerserPlugin({
  sourceMap: scriptsSourceMap,
  parallel: true,
  cache: true,
  terserOptions,
}));

使用ng build frontend --prod重建应用程序，您应该能够在控制台中看到哪些服务无法注入。

Answer 4

您尝试访问服务但未在模块中提供

Answer 5

我不想放弃优化，因为捆绑包的大小大约增加了8倍。

幸运的是，事实证明这是一件愚蠢的事情：）我的组件之一中有provider：[]节，当我删除它时，错误消失了。

希望这可能对某人有用！

Answer 6

对于错误：NullInjectorError：t 没有提供者！ （注意：仅对于提供者为“t”的错误，如果它是另一个提供者，则可能是因为没有声明 app.module -> provider []）

问题出现在我用ng“ng build --prod”编译时，切换到“npm run build --prod”问题消失了。

尝试用其他版本或 npm 编译

Answer 7

我有这个“错误：NullInjectorError：t 没有提供者！”问题，因为我在 app.module 中导入 ReactiveFormsModule 之前使用了 FormBuilder