小编Web*_*ter的帖子

我刚刚在Angular项目中安装了ng-bootstrap，然后添加了它的模块。但是我的CLI向我显示一个错误。

“在./node_modules/@ng-bootstrap/ng-bootstrap/fesm5/ng-bootstrap.js 9853：57-75中的警告“在'@ angular / core'中找不到导出'?? defineInjectable'”

app.module

import {NgbModule} from '@ng-bootstrap/ng-bootstrap';
import {NgbPaginationModule, NgbAlertModule} from '@ng-bootstrap/ng-bootstrap';

@NgModule({
  imports: [
    CommonModule,
    NgxPaginationModule,
    NgbModule,
    NgbPaginationModule,
    NgbAlertModule,
    RouterModule.forChild(routes)
  ],

Package.json

{
  "name": "eastlaw",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "^6.1.10",
    "@angular/cdk": "^8.0.1",
    "@angular/common": "^6.1.0",
    "@angular/compiler": "^6.1.0",
    "@angular/core": "^6.1.0",
    "@angular/forms": "^6.1.0",
    "@angular/http": "^6.1.0",
    "@angular/material": "^8.0.1",
    "@angular/platform-browser": "^6.1.0",
    "@angular/platform-browser-dynamic": "^6.1.0",
    "@angular/router": "^6.1.0",
    "@ng-bootstrap/ng-bootstrap": …

我ReactiveForms在我的 Angular 应用程序中使用。我想如果用户输入的数字少于 7 个，所以应该在那里显示错误消息，但不幸的是，如果有任何错误或解决方案，它就不起作用，所以请提供给我。谢谢

服务.ts

PhoneNo: ['', [Validators.required, Validators.minLength(7)]],

html

<input class="full-width has-padding has-border" formControlName="PhoneNo" type="tel" placeholder="Mobile *" />
        <img src="../../../../assets/img/required-img.png" class="required-img"
          *ngIf="service.formModel.get('PhoneNo').touched && service.formModel.get('PhoneNo').errors?.required"
          title="This fields is mandatory" data-toggle="tooltip" />
          <label *ngIf="service.formModel.get('PhoneNo').touched && service.formModel.get('PhoneNo').errors?.minLength">Minimum 7 characters required</label>