angular-docs-cn/aio/content/errors/NG8003.md

@name Missing Reference Target @category compiler @shortDescription No directive found with export

@description Angular can’t find a directive with {{ PLACEHOLDER }} export name. This is common with a missing import or a missing exportAs on a directive.

@debugging Use the string name of the export not found to trace the templates or modules using this export.

Ensure that all dependencies are properly imported and declared in our Modules. For example, if the export not found is ngForm, we will need to import FormsModule and declare it in our list of imports in *.module.ts to resolve the missing export error.

import { FormsModule } from '@angular/forms';

@NgModule({
  ...
  imports: [
    FormsModule,
    …

If you recently added an import, you will need to restart your server to see these changes.

This is a duplicate issue of a NG0301: Export Not Found.