Angular开发问题：Uncaught Error: Component UserComponent is not part of any NgModule

Angular开发问题：Uncaught Error: Component UserComponent is not part of any NgModule

异常问题:

用angular开发项目时候比较常见错误，打开浏览器，页面刷新不出来，控制台报错：

Uncaught Error: Component UserComponent is not part of any NgModule or the module has not been imported into your module.
at JitCompiler.push…/node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._createCompiledHostTemplate (vendor.js:62394)
at vendor.js:62370
at Array.forEach ()
at vendor.js:62367
at Array.forEach ()
at JitCompiler.push…/node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._compileComponents (vendor.js:62356)
at vendor.js:62284
at Object.then (vendor.js:39005)
at JitCompiler.push…/node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._compileModuleAndComponents (vendor.js:62283)
at JitCompiler.push…/node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler.compileModuleAsync (vendor.js:62243)

错误原因：

访问对应url时候，UserComponent 没有在NgModule 导入配置中，浏览器找不到组件造成。

解决办法：

将UserComponent加入到AppModulel类中，刷新页面即可。

@NgModule({
  declarations: [
    AppComponent,
    LoginComponent,
    PageNotFoundComponent,
    IndexComponent,
    MainComponent,
    LeftNavComponent,
    LeftMenuClickPopup,
    ManpowerInputComponent,
    ManpowerAddComponent,
    ManpowerUserlistComponent,
    UserDialogComponent,
    UserComponent,
    RoleComponent,
    RightComponent
  ],