1009
votes

THE SITUATION:

Please help! I am trying to make what should be a very simple form in my Angular2 app but no matter what it never works.

ANGULAR VERSION:

Angular 2.0.0 Rc5

THE ERROR:

Can't bind to 'formGroup' since it isn't a known property of 'form'

enter image description here

THE CODE:

The view:

<form [formGroup]="newTaskForm" (submit)="createNewTask()">
   <div class="form-group">
      <label for="name">Name</label>
      <input type="text" name="name" required>
   </div>
   <button type="submit" class="btn btn-default">Submit</button>
</form>

The controller:

import { Component } from '@angular/core';
import { FormGroup, FormControl, Validators, FormBuilder }  from '@angular/forms';
import {FormsModule,ReactiveFormsModule} from '@angular/forms';
import { Task } from './task';

@Component({
    selector: 'task-add',
    templateUrl: 'app/task-add.component.html'

})
export class TaskAddComponent {

    newTaskForm: FormGroup;

    constructor(fb: FormBuilder) 
    {
        this.newTaskForm = fb.group({
            name: ["", Validators.required]
        });
    }

    createNewTask()
    {
        console.log(this.newTaskForm.value)
    } 
}

The ngModule:

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule }   from '@angular/forms';

import { routing }        from './app.routing';
import { AppComponent }  from './app.component';
import { TaskService } from './task.service'

@NgModule({
    imports: [ 
        BrowserModule,
        routing,
        FormsModule
    ],
    declarations: [ AppComponent ],
    providers: [
        TaskService
    ],
    bootstrap: [ AppComponent ]
})
export class AppModule { }

THE QUESTION:

Why am I getting that error?

Am I missing something?

30
Make sure that you import the ReactiveFormsModule to the module you use forms with ( for instance auth.module , form.module ) not the app.module . angular.io/guide/reactive-formsHossam Maher

30 Answers

1698
votes

RC5 FIX

You need to import { REACTIVE_FORM_DIRECTIVES } from '@angular/forms' in your controller and add it to directives in @Component. That will fix the problem.

After you fix that, you will probably get another error because you didn't add formControlName="name" to your input in form.

RC6/RC7/Final release FIX

To fix this error, you just need to import ReactiveFormsModule from @angular/forms in your module. Here's the example of a basic module with ReactiveFormsModule import:

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { AppComponent }  from './app.component';

@NgModule({
    imports: [
        BrowserModule,
        FormsModule,
        ReactiveFormsModule
    ],
    declarations: [
        AppComponent
    ],
    bootstrap: [AppComponent]
})

export class AppModule { }

To explain further, formGroup is a selector for directive named FormGroupDirective that is a part of ReactiveFormsModule, hence the need to import it. It is used to bind an existing FormGroup to a DOM element. You can read more about it on Angular's official docs page.

182
votes

Angular 4 in combination with feature modules (if you are for instance using a shared-module) requires you to also export the ReactiveFormsModule to work.

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';

@NgModule({
  imports:      [
    CommonModule,
    ReactiveFormsModule
  ],
  declarations: [],
  exports: [
    CommonModule,
    FormsModule,
    ReactiveFormsModule
  ]
})
export class SharedModule { } 
151
votes

Ok after some digging I found a solution for "Can't bind to 'formGroup' since it isn't a known property of 'form'."

For my case, I've been using multiple modules files, i added ReactiveFormsModule in app.module.ts

 import { FormsModule, ReactiveFormsModule } from '@angular/forms';`

@NgModule({
  declarations: [
    AppComponent,
  ]
  imports: [
    FormsModule,
    ReactiveFormsModule,
    AuthorModule,
],
...

But this wasn't working when I use a [formGroup] directive from a component added in another module, e.g. using [formGroup] in author.component.ts which is subscribed in author.module.ts file:

import { NgModule }       from '@angular/core';
import { CommonModule }   from '@angular/common';
import { AuthorComponent } from './author.component';

@NgModule({
  imports: [
    CommonModule,
  ],
  declarations: [
    AuthorComponent,
  ],
  providers: [...]
})

export class AuthorModule {}

I thought if i added ReactiveFormsModule in app.module.ts, by default ReactiveFormsModule would be inherited by all its children modules like author.module in this case... (wrong!). I needed to import ReactiveFormsModule in author.module.ts in order to make all directives to work:

...
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
...

@NgModule({
  imports: [
    ...,
    FormsModule,    //added here too
    ReactiveFormsModule //added here too
  ],
  declarations: [...],
  providers: [...]
})

export class AuthorModule {}

So, if you are using submodules, make sure to import ReactiveFormsModule in each submodule file. Hope this helps anyone.

63
votes

I have encountered this error during unit testing of a component (only during testing, within application it worked normally). The solution is to import ReactiveFormsModule in .spec.ts file:

// Import module
import { ReactiveFormsModule } from '@angular/forms';

describe('MyComponent', () => {
    beforeEach(async(() => {
        TestBed.configureTestingModule({
            declarations: [MyComponent],
            imports: [ReactiveFormsModule],  // Also add it to 'imports' array
        })
        .compileComponents();
    }));
});
26
votes

The suggested answer did not work for me with Angular 4. Instead I had to use another way of attribute binding with the attr prefix:

<element [attr.attribute-to-bind]="someValue">
24
votes

The error says that FormGroup is not recognized in this module. So You have to import these(below) modules in every module that uses FormGroup

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

Then add FormsModule and ReactiveFormsModule into your Module's imports array.

imports: [
  FormsModule,
  ReactiveFormsModule
],

You may be thinking that I have already added it in AppModule and it should inherit from it? But it is not. because these modules are exporting required directives that are available only in importing modules. Read more here... https://angular.io/guide/sharing-ngmodules.

Other factors for these errors may be spell error like below...

[FormGroup]="form" Capital F instead of small f

[formsGroup]="form" Extra s after form

19
votes

If you have to import two modules then add like this below

import {ReactiveFormsModule,FormsModule} from '@angular/forms';
@NgModule({
  declarations: [
    AppComponent,
    HomeComponentComponent,
    BlogComponentComponent,
    ContactComponentComponent,
    HeaderComponentComponent,
    FooterComponentComponent,
    RegisterComponent,
    LoginComponent
  ],
  imports: [
    BrowserModule,
    FormsModule,
    HttpModule,
    routes,
    ReactiveFormsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
15
votes

Keep in mind that if you have defined "Feature Modules", you'll need to import in the Feature Module, even if you already imported to the AppModule. From the Angular documentation:

Modules don't inherit access to the components, directives, or pipes that are declared in other modules. What AppModule imports is irrelevant to ContactModule and vice versa. Before ContactComponent can bind with [(ngModel)], its ContactModule must import FormsModule.

https://angular.io/docs/ts/latest/guide/ngmodule.html

14
votes

I had the same issue with Angular 7. Just import following in your app.module.ts file.

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

Then add FormsModule and ReactiveFormsModule in to your imports array.

imports: [
  FormsModule,
  ReactiveFormsModule
],
11
votes

This problem occurs due to missing import of FormsModule,ReactiveFormsModule .I also came with same problem. My case was diff. as i was working with modules.So i missed above imports in my parent modules though i had imported it into child modules,it wasn't working.

Then i imported it into my parent modules as below, and it worked!

import { ReactiveFormsModule,FormsModule  } from '@angular/forms';
import { AlertModule } from 'ngx-bootstrap';

         @NgModule({
          imports: [
            CommonModule,
            FormsModule,
            ReactiveFormsModule,
    ],
      declarations: [MyComponent]
    })
8
votes

I was coming across this error when trying to do e2e testing and it was driving me crazy that there were no answers to this.

IF YOU ARE DOING TESTING, find your *.specs.ts file and add :

import {ReactiveFormsModule, FormsModule} from '@angular/forms';
7
votes

For people strolling these threads about this error. In my case I had a shared module where I only exported the FormsModule and ReactiveFormsModule and forgot to import it. This caused a strange error that formgroups were not working in sub components. Hope this helps people scratching their heads.

7
votes

Don't be a dumb dumb like me. Was getting the same error as above, NONE of the options in this thread worked. Then I realized I capitalized 'F' in FormGroup. Doh!

Instead Of:

[FormGroup]="form"

Do:

[formGroup]="form"
6
votes

A LITTLE NOTE: Be careful about loaders and minimize (Rails env.):

After seeing this error and trying every solution out there, i realised there was something wrong with my html loader.

I've set my Rails environment up to import HTML paths for my components successfully with this loader (config/loaders/html.js.):

module.exports = {
  test: /\.html$/,
  use: [ {
    loader: 'html-loader?exportAsEs6Default',
    options: {
      minimize: true
    }
  }]
}

After some hours efforts and countless of ReactiveFormsModule imports i saw that my formGroup was small letters: formgroup.

This led me to the loader and the fact that it downcased my HTML on minimize.

After changing the options, everything worked as it should, and i could go back to crying again.

I know that this is not an answer to the question, but for future Rails visitors (and other with custom loaders) i think this could be helpfull.

6
votes

Import and register ReactiveFormsModule in your app.module.ts.

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

@NgModule({
declarations: [
AppComponent,
HighlightDirective,
TestPipeComponent,
ExpoentialStrengthPipe

],
imports: [
BrowserModule,
ReactiveFormsModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }

Make sure your spelling is correct in both .ts and .html file. xxx.ts

  profileForm = new FormGroup({
  firstName: new FormControl(''),
 lastName: new FormControl('')
 });

xxx.html file-

  <form [formGroup]="profileForm"> 
  <label>
  First Name:
   <input type="text" formControlName = "firstName">
  </label>

  <label>
  Last Name:
   <input type="text" formControlName = "lastName">
   </label>
   </form>

I was by mistake wrote [FormGroup] insted of [formGroup]. Check your spelling correctly in .html. It doesn't throw compile time error If anything wrong in .html file.

5
votes

using and import REACTIVE_FORM_DIRECTIVES:

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { AppComponent }  from './app.component';

@NgModule({
    imports: [
        BrowserModule,
        FormsModule,
        ReactiveFormsModule
    ],
    declarations: [
        AppComponent
    ],
    bootstrap: [AppComponent]
})

export class AppModule { }
5
votes

If you have this problem when you developing a component so you should add these two modules to your closest module :

import { FormsModule, ReactiveFormsModule } from '@angular/forms';
@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
   // other modules
    FormsModule,
    ReactiveFormsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

And if you are developing a test for your components so you should add this module to your test file like this:

import { async, ComponentFixture, TestBed } from '@angular/core/testing';
import { ContactusComponent } from './contactus.component';
import { ReactiveFormsModule } from '@angular/forms';

describe('ContactusComponent', () => {
  let component: ContactusComponent;
  let fixture: ComponentFixture<ContactusComponent>;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ContactusComponent],
      imports:[
        ReactiveFormsModule
      ]

    })
      .compileComponents();
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(ContactusComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });

  it('should create', () => {
    expect(component).toBeTruthy();
  });
});
5
votes

Import ReactiveFormsModule in the corresponded module

5
votes

I had the same problem, make sure that if using submodules (for example, you not only have app.component.module.ts, but you have a separate component such as login.module.ts, that you include ReactiveFormsModule import in this login.module.ts import, for it to work. I don't even have to import ReactiveFormsModule in my app.component.module because I'm using submodules for everything.

login.module.ts:

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';

import { IonicModule } from '@ionic/angular';

import { LoginPageRoutingModule } from './login-routing.module';

import { LoginPage } from './login.page';

@NgModule({
  imports: [
    CommonModule,
    FormsModule,
    ReactiveFormsModule,
    IonicModule,
    LoginPageRoutingModule
  ],
  declarations: [LoginPage]
})
export class LoginPageModule {}
5
votes

Simple solution :

step 1: import ReactiveFormModule

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

step 2: add "ReactiveFormsModule" to import section

imports: [

    ReactiveFormsModule
  ]

Step 3: restart App and Done

Example :

import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import {ReactiveFormsModule} from '@angular/forms';
import { EscalationManagementRoutingModule } from './escalation-management-routing.module';
import { EscalationManagementRouteWrapperComponent } from './escalation-management-route-wrapper.component';


@NgModule({
  declarations: [EscalationManagementRouteWrapperComponent],
  imports: [
    CommonModule,
    EscalationManagementRoutingModule,
    ReactiveFormsModule
  ]
})
export class EscalationManagementModule { }
4
votes

Might help someone:

when you have a formGroup in a modal (entrycomponent), then you have to import ReactiveFormsModule also in the module where the modal is instantiated.

4
votes

Note: if you are working inside child module's component, then you just have to import ReactiveFormsModule in child module rather than parent app root module.

3
votes

if this is just a typescript error but everything on your form works,you may just have to restart your IDE

3
votes
  1. Your Angular version is 11+, and you use VisualStudioCode?

  2. And you have already imported FormsModule, ReactiveFormsModule and added it into your imports-section within app.module.ts:

// app.module.ts (excerpt)
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
imports: [
  ...
  FormsModule,
  ReactiveFormsModule,
  ...
],
  1. And you have the right imports (sometimes there are other libs with similar names), you have defined and initialized your form in your component?
// MyWonderfulComponent (excerpt)


import { FormBuilder, FormGroup, Validators } from '@angular/forms';

export class MyWonderfulComponent implements OnInit {
  form: FormGroup; 
  ...
  constructor (private fb: FormBuilder) {
    this.form = this.fb.group({
      // DON'T FORGET THE FORM INITIALISATION
    });
  }
  1. Your Component-Template has your form:
<form [formGroup]="form" (ngSubmit)="submit()">
  <!-- MY FORM CONTROLS ARE ALREADY HERE --> 
</form>
  1. And you still get the error message "...since it isn't a known property of..." ?

then just simple restart your VisualStudioCode :)

2
votes

Can't bind to 'formGroup' since it isn't a known property of 'form'

means that you try to bind a property using angular ([prop]) but angular cant find anything he knows for that element (in this case form).

this can happen by not using the right module (missing an import somewhere in the way) and sometimes just cause a typo like:

[formsGroup], with s after form

2
votes

Firstly, it is not related to Angular versions>2. Just import following in your app.module.ts file will fix the problems.

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

Then add FormsModule and ReactiveFormsModule in to your imports array.

imports: [
  FormsModule,
  ReactiveFormsModule
],

Note : You can also import ReactiveFormsModule to specific module instead to app.module.ts

2
votes

import { FormsModule, ReactiveFormsModule } from '@angular/forms'; and add it in imports array in the app-module.ts file.

2
votes

You can get this error message even if you have already imported FormsModule and ReactiveFormsModule. I moved a component (that uses the [formGroup] directive) from one project to another, but failed to add the component to the declarations array in the new module. That resulted in the Can't bind to 'formGroup' since it isn't a known property of 'form' error message.

2
votes

I've been struggling with this error during the last 3 days. I added the ReactiveFormsModule and FormsModule as mentionned in the comments above in both of my modules but it had no effect until I reloaded my project with another "ng serve". I don't know why it didn't reload automatically but at least i'm glad it worked finally! Any explanation please?

2
votes

You need to import the FormsModule, ReactiveFormsModule in this module as well as the top level.

If you used a reactiveForm in another module then you've to do also this step along with above step: import also reactiveFormsModule in that particular module.

For example:

imports: [
  BrowserModule,
  FormsModule,
  ReactiveFormsModule,
  AppRoutingModule,
  HttpClientModule,
  BrowserAnimationsModule
],