The 'formGroup' property cannot be bound as it is not recognized as a valid property of 'form' in Angular 7

Question

The 'formGroup' property cannot be bound as it is not recognized as a valid property of 'form' in Angular 7

I tried implementing a login feature using web API with Angular 7, but encountered an error when using

<form [formGroup]="loginForm" (submit)="loginFormSubmit()">

. What could be causing this issue?

https://i.sstatic.net/3M2a5.jpg

login.component.html

<form [formGroup]="loginForm" (submit)="loginFormSubmit()">              
                <h2 class="text-center red heading text-heading">LOGIN</h2>
                <div class="form-group custom-input">
                    <div>
                        <span style="color: #D56161;" class="lblMessage"></span>
                    </div><br>
                    <div class="input-group">
                        <div class="input-group-prepend">
                        <span class="input-group-text">
                            <i class="fa fa-user"></i>
                        </span>
                    </div>
                        <input class="form-control" data-val="true" data-val-required="required" formControlName="userId" placeholder="Username" type="text" value="">
                    <small class="text-danger" *ngIf="loginForm.form-control.userId.invalid && (loginFormSubmitted  || loginForm.controls.userId.touched)">Required</small>
                    </div>
                    <div style="text-align:left">
                        <span class="field-validation-valid" data-valmsg-for="UserName" data-valmsg-replace="true" style="color:#D56161;"></span>
                    </div>
                </div>
                <div class="form-group">
                    <div class="input-group">
                    <div class="input-group-prepend">
                        <span class="input-group-text">
                            <i class="fa fa-lock"></i>
                        </span>
                    </div>
                        <input class="form-control" data-val="true" data-val-required="required" id="Password" formControlName="Password" placeholder="Password" type="password">
                        <small class="text-danger" *ngIf="loginForm.controls.password.invalid && (loginFormSubmitted || loginForm.controls.password.invalid)">Required</small>
                    </div>
                    <div style="text-align:left">
                        <span class="field-validation-valid" data-valmsg-for="Password" data-valmsg-replace="true" style="color:#D56161;"></span>
                    </div>
                </div>
                <div class="form-group">
                    <button type="submit" class="btn btn-block btn-primary button login" [disabled]="loginFormSubmitted">LOGIN <i class="fa fa-arrow-right"></i></button>
                </div>
                <hr>
                <div class="row">
                    <div class="col-lg-12">
                        <a class="float-left" href="/Admin/ForgotPassword">Forgot Password?</a>
                        <a class="float-right" href="">Back to Website</a>
                    </div>
                </div>
            </form>

login.component.ts

import { Component } from '@angular/core';
import { ApiService } from '../../../../services/api/api.service';
import { Observable } from 'rxjs';

@Component({
    selector: 'app-login',
    templateUrl: './login.component.html'
})

export class loginComponent{

    users$: object;

    constructor(private data: ApiService){
    }

    ngOnInit(){

    }

    loginFormSubmit(){
        alert('login alert');
    }

}

What steps can I take to address this issue?

Appreciate any guidance!

angular typescript angular7

Answer 1

Answer №1

To start, you need to establish a formGroup in the login.ts file.

Begin by importing the Forms Module and Reactive forms module into the module where the login component is declared. This step should resemble the following:

import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { BrowserModule } from '@angular/platform-browser';

@NgModule({
  declarations: [
    loginComponent
  ],
  imports: [
    BrowserModule,
    ReactiveFormsModule,

  ],

  bootstrap: [AppComponent]
})
export class AppModule { }

Proceed to the login.ts file and create a form group. Here is an example using the form builder method, but other methods can also be utilized. For more detailed guidance, refer to the link provided below: angular reactive forms

import { Component, OnInit } from '@angular/core';
import { FormGroup, FormControl, FormBuilder } from '@angular/forms';

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

@Component({
  // add your meta data here
})
export class loginComponent implements OnInit {

  constructor(fb:FormBuilder) { }

  ngOnInit() {
  }

  private loginForm = this.fb.group({
    userId: ['',],
    // add other form controls within the group

  });

}

Answer 2

To start, you need to establish a formGroup in the login.ts file.

Begin by importing the Forms Module and Reactive forms module into the module where the login component is declared. This step should resemble the following:

import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { BrowserModule } from '@angular/platform-browser';

@NgModule({
  declarations: [
    loginComponent
  ],
  imports: [
    BrowserModule,
    ReactiveFormsModule,

  ],

  bootstrap: [AppComponent]
})
export class AppModule { }

Proceed to the login.ts file and create a form group. Here is an example using the form builder method, but other methods can also be utilized. For more detailed guidance, refer to the link provided below: angular reactive forms

import { Component, OnInit } from '@angular/core';
import { FormGroup, FormControl, FormBuilder } from '@angular/forms';

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

@Component({
  // add your meta data here
})
export class loginComponent implements OnInit {

  constructor(fb:FormBuilder) { }

  ngOnInit() {
  }

  private loginForm = this.fb.group({
    userId: ['',],
    // add other form controls within the group

  });

}

Answer 3

Answer №2

If you encounter an error in the debugger stating that formGroup is not defined in pure HTML, don't worry - you can resolve this by importing ReactiveFormsModule from the @angular/forms package into your project. The [formGroup] directive is provided and exported by ReactiveFormsModule.

Since the [formGroup] directive is exported by ReactiveFormsModule, you can use it in any component within a Module that imports ReactiveFormsModule.

The formGroup directive includes an @Input property called formGroup. By binding the instance of your formGroup in the TypeScript file to this @Input property inside the formGroup directive, you are properly connecting the two.

It's important to note that the formGroup directive from ReactiveFormsModule acts as a child for your component. To communicate with a child component in Angular, utilize property binding like you are doing here.

This pattern of property binding and event binding is commonly used throughout the Angular framework, making it essential to understand for working effectively with Angular 2+.

Answer 4

If you encounter an error in the debugger stating that formGroup is not defined in pure HTML, don't worry - you can resolve this by importing ReactiveFormsModule from the @angular/forms package into your project. The [formGroup] directive is provided and exported by ReactiveFormsModule.

Since the [formGroup] directive is exported by ReactiveFormsModule, you can use it in any component within a Module that imports ReactiveFormsModule.

The formGroup directive includes an @Input property called formGroup. By binding the instance of your formGroup in the TypeScript file to this @Input property inside the formGroup directive, you are properly connecting the two.

It's important to note that the formGroup directive from ReactiveFormsModule acts as a child for your component. To communicate with a child component in Angular, utilize property binding like you are doing here.

This pattern of property binding and event binding is commonly used throughout the Angular framework, making it essential to understand for working effectively with Angular 2+.

The 'formGroup' property cannot be bound as it is not recognized as a valid property of 'form' in Angular 7

Answer №1

Answer №2

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