Class is using Angular features but is not decorated in angular 14

Question

I have updated my angular app from 13 to 14. After update i am getting below error after opening component class in vs code.

Class is using Angular features but is not decorated. Please add an explicit Angular decorator

I have checked this question

But i have not using any ineritance in the app.

But the application run perfectly. How to remove that error?

ts.confing

/* To learn more about this file see: https://angular.io/config/tsconfig . */

{
  "compileOnSave": false,
  "compilerOptions": {
    
    "baseUrl": "./",
    "outDir": "./dist/out-tsc",
    "forceConsistentCasingInFileNames": false,
    "strict": false,
    "allowSyntheticDefaultImports":true, 
    "noImplicitOverride": true,
    "noPropertyAccessFromIndexSignature": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "sourceMap": true,
    "declaration": true,
    "downlevelIteration": true,
    "experimentalDecorators": true,
    "moduleResolution": "node",
    "importHelpers": true,
    "target": "es2022",
    "module": "es2022",
    "lib": [
      "es2022",
      "dom"
    ],
    "paths": {
      "stream": [ "./node_modules/stream-browserify" ]
    },
  },
  "angularCompilerOptions": {
    "enableI18nLegacyMessageIdFormat": false,
    "strictInjectionParameters": true,
    "strictInputAccessModifiers": true,
    "strictTemplates": false,
  }
}

Validation component

import { Component, Input } from '@angular/core';
import { AbstractControl } from '@angular/forms';
import { ValidationService } from 'src/app/core/services/validation.service';

@Component({
  selector: 'app-validation-message',
  template: '<div *ngIf="errorMessage !== null" style="width:50%;margin-top:.25rem;font-size:80%;color:#dc3545">{{errorMessage}}</div>'
})

export class ValidationMessageComponent {
  @Input() control: AbstractControl;

  constructor() {
  }

  get errorMessage() {
    if (this.control.errors) {
    
      for (let propertyName in this.control.errors) {
        if (this.control.errors.hasOwnProperty(propertyName) && this.control.touched) {
          return ValidationService.getValidatorErrorMessage(propertyName, this.control.errors[propertyName]);
        }
      }
    }
    return null;
  }
}

Answer 1

Had the same issue. Typescript downgrade from 4.7.4 to 4.7.2 resolved the problem.

npm i typescript@4.7.2

Answer 2

it is due to Angular Language Service extension, it does not support Typescript 4.8 yet, see related issue here: https://github.com/angular/vscode-ng-language-service/issues/1746

Answer 3

I had the same problem, i resolve it by downgrading typescript dependencies:

"@typescript-eslint/eslint-plugin": "5.29.0",
"@typescript-eslint/parser": "5.29.0",
"typescript": "4.7.2"

now the error is gone and all is working perfectly

Answer 4

Same issue with Angular 15. This time upgrading typescript from 4.8.2 to 4.8.4 solved the problem.

Answer 5

initially i had typescript 4.8.4 when hitting this problem. after i read through here, I downgraded to 4.7.2, didn't work; then I went back to 4.8.4, interestingly it worked.