Form control problem with angular Material - javascript

I have this message appear in my console when I want edit my user.
I see some solution on the web, Some people have trouble with it but no solution for me.
Does someone have the same problem ?
EditUserDialogComponent.html:37 ERROR Error:
ngModel cannot be used to register form controls with a parent formGroup directive. Try using
formGroup's partner directive "formControlName" instead. Example:
<div [formGroup]="myGroup">
<input formControlName="firstName">
</div>
In your class:
this.myGroup = new FormGroup({
firstName: new FormControl()
});
Or, if you'd like to avoid registering this form control, indicate that it's standalone in ngModelOptions:
Example:
<div [formGroup]="myGroup">
<input formControlName="firstName">
<input [(ngModel)]="showMoreControls" [ngModelOptions]="{standalone: true}">
</div>
at Function.modelParentException (forms.js:6182)
at NgModel._checkParentType (forms.js:6754)
at NgModel._checkForErrors (forms.js:6740)
at NgModel.ngOnChanges (forms.js:6640)
at checkAndUpdateDirectiveInline (core.js:31905)
at checkAndUpdateNodeInline (core.js:44366)
at checkAndUpdateNode (core.js:44305)
at debugCheckAndUpdateNode (core.js:45327)
at debugCheckDirectivesFn (core.js:45270)
at Object.eval [as updateDirectives] (EditUserDialogComponent.html:42)
and this is my HTML,
I think it's a problem about the form control, but if I follow the instructions of the error message,
I have the same...
<div class="manage-content">
<div class="title">
<mat-icon class="user-icon">how_to_reg</mat-icon>
<h3>Edit a user</h3>
</div>
<form [formGroup]="form" (ngSubmit)="onSubmit()">
<mat-form-field class="full-width-input">
<input id="firstName" matInput placeholder="First name" formControlName="f_name" [(ngModel)]="selectedUser.f_name"#f_name>
<mat-error *ngIf="isFieldInvalid('f_name')">
The first name you've entered is malformed.
</mat-error>
</mat-form-field>
<mat-form-field class="full-width-input">
<input id="middleName" matInput placeholder="Middle name" formControlName="m_name" [(ngModel)]="selectedUser.m_name" #m_name>
<mat-error *ngIf="isFieldInvalid('m_name')">
The middle name you've entered is malformed.
</mat-error>
</mat-form-field>
<mat-form-field class="full-width-input">
<input id="lastName" matInput placeholder="Last name" formControlName="l_name" [(ngModel)]="selectedUser.l_name" #l_name>
<mat-error *ngIf="isFieldInvalid('l_name')">
The last name you've entered is malformed.
</mat-error>
</mat-form-field>
<mat-form-field class="full-width-input">
<input id="email" matInput placeholder="Email" formControlName="email" [(ngModel)]="selectedUser.email" #email>
<mat-error *ngIf="isFieldInvalid('email')">
The email you've entered is malformed.
</mat-error>
</mat-form-field>
<mat-form-field class="full-width-input">
<div class="visibility">
<input id="password" matInput type="password" placeholder="Password" formControlName="password" [(ngModel)]="selectedUser.password">
<mat-icon *ngIf="isPasswordVisible" (click)=showPassword()>visibility</mat-icon>
<mat-icon *ngIf="!isPasswordVisible" (click)="showPassword()">visibility_off</mat-icon>
</div>
<mat-error *ngIf="isFieldInvalid('password')">
The password you've entered is malformed.
</mat-error>
</mat-form-field>
<mat-form-field>
<mat-select placeholder="Role" class="full-width-input" [(ngModel)]="selectedUser.role">
<mat-option value="option">End-User</mat-option>
<mat-option value="option">View-User</mat-option>
<mat-option value="option">Vendor</mat-option>
<mat-option value="option">Tool Guy</mat-option>
</mat-select>
</mat-form-field>
<div class="cta-btn">
<button mat-raised-button class="createUserBtn" color="primary" type="submit">Update user</button>
<button mat-raised-button class="createUserBtn" color="warn" type="submit" (click)="click()">Cancel</button>
</div>
</form>
</div>
#Component({
selector: 'app-edit-user-dialog',
templateUrl: 'edit-user-dialog.component.html',
styleUrls: ['./manage-user.component.scss']
})
export class EditUserDialogComponent {
form: FormGroup;
formSubmitAttempt: boolean;
isPasswordVisible = false;
selectedUser: User;
constructor(private formBuilder: FormBuilder, private userService: UserService, public dialog: MatDialog, public dialogRef: MatDialogRef<EditUserDialogComponent>,
#Inject(MAT_DIALOG_DATA) public data: any) {
this.selectedUser = data;
console.log(this.selectedUser);
this.form = this.formBuilder.group({
email: ['', Validators.compose([Validators.required, Validators.pattern('^[a-zA-Z0-9_.+-]+#[a-zA-Z0-9-]+\\.[a-zA-Z0-9-.]+$')])],
password: ['', Validators.compose([Validators.required, Validators.minLength(10), Validators.maxLength(35)])],
f_name: ['', Validators.compose([Validators.required, Validators.maxLength(100)])],
m_name: ['', Validators.compose([Validators.maxLength(100), Validators.pattern('[0-9]+')])],
l_name: ['', Validators.compose([Validators.required, Validators.maxLength(100)])]
// client: ['', Validators.compose([Validators.required, Validators.minLength(10), Validators.maxLength(35)])],
});
}
click(): void {
this.dialogRef.close();
}
showPassword() {
const pass: HTMLInputElement = document.getElementById('password') as HTMLInputElement;
if (pass.type === "password") {
this.isPasswordVisible = true;
pass.type = "text";
} else {
this.isPasswordVisible = false;
pass.type = "password";
}
}
isFieldInvalid(field: string) {
return (
(!this.form.get(field).valid && this.form.get(field).touched) ||
(this.form.get(field).untouched && this.formSubmitAttempt)
);
}
onSubmit() {
// if (this.form.valid) {
// this.authService.login(this.form.value);
// }
this.formSubmitAttempt = true;
}
}
thanks a lot for your help

The issue you are having is the usage of the ([ngModel]) inside of a formGroup.
If you need to extract a value, you will have to do it via the formGroup variable on the TS component.
Check out more information on the Angular support page: https://angular.io/guide/reactive-forms

change this:
`<input id="password" matInput type="password" placeholder="Password" formControlName="password" [(ngModel)]="selectedUser.password">`
into this:
`<input id="password" matInput type="password" placeholder="Password" formControlName="password" (change)="selectedUserChanged($event)">`
//and add to your ts
`selectedUserChanged(change: any) {
this.group.get('password').setValue(change.value);
}`

Related

Problems with custom form validator in angular

I create custom form validator for checking equality of password, I mean it checks if the passwords are matching. I can't get a real true or false in my html(variable=signupForm.valid ). Maybe I need to pass on different way controlValuesAreEqual in my form, or there is problem with imports all these forms and validators?
Ts file:
import { HttpClient } from '#angular/common/http';
import { Component, OnInit } from '#angular/core';
import { UntypedFormGroup, UntypedFormBuilder, Validators, ValidatorFn, AbstractControl, ValidationErrors, FormGroup } from '#angular/forms';
import { Router } from '#angular/router';
#Component({
selector: 'app-signup',
templateUrl: './signup.component.html',
styleUrls: ['./signup.component.scss'],
})
export class SignupComponent implements OnInit {
public signupForm!: UntypedFormGroup;
constructor(
private formBuilder: UntypedFormBuilder,
private http: HttpClient,
private router: Router
) {}
ngOnInit(): void {
this.signupForm = this.formBuilder.group({
email: ['', Validators.required],
name: ['', Validators.required],
password: ['', Validators.required],
confirmPassword: ['',Validators.required],
validators: this.controlValuesAreEqual('password', 'confirmPassword')
});
}
private controlValuesAreEqual(controlNameA: string, controlNameB: string): ValidatorFn {
return (control: AbstractControl): ValidationErrors | null => {
const formGroup = control as FormGroup
const valueOfControlA = formGroup.get(controlNameA)?.value
const valueOfControlB = formGroup.get(controlNameB)?.value
if (valueOfControlA === valueOfControlB) {
return null
} else {
return { valuesDoNotMatch: true }
}
}
}
signUp() {
this.http
.post<any>('http://localhost:3000/signupUsers', this.signupForm.value)
.subscribe({
next: (res) => {
this.signupForm.reset(), this.router.navigate(['login']);
},
error: (e) => alert('Something went wrong'),
});
}
}
And HTML is here
<div class="container mt-5">
<div class="card" style="padding: 20px">
<h2 class="text-center">Please Sign Up!</h2>
<form [formGroup]="signupForm" (ngSubmit)="signUp()">
<mat-form-field appearance="outline" class="w-100">
<mat-label>Email</mat-label>
<input formControlName="email" matInput placeholder="E-Mail" />
<mat-hint>Hint</mat-hint>
</mat-form-field>
<mat-form-field appearance="outline" class="w-100">
<mat-label>Name</mat-label>
<input formControlName="name" matInput placeholder="name" />
<mat-hint>Hint</mat-hint>
</mat-form-field>
<mat-form-field appearance="outline" class="w-100">
<mat-label>Password</mat-label>
<input
type="password"
formControlName="password"
matInput
placeholder="password"
/>
<mat-hint>Hint</mat-hint>
</mat-form-field>
<mat-form-field appearance="outline" class="w-100">
<mat-label>Confirm Password</mat-label>
<input
type="password"
formControlName="confirmPassword"
matInput
placeholder="password"
/>
<mat-hint align="start">
<strong>{{ signupForm.valid }}</strong>
</mat-hint>
</mat-form-field>
<button type="submit" mat-raised-button color="primary" class="w-100">
Sign Up
</button>
</form>
<a style="text-decoration: none; margin-top: 10px" routerLink="/login"
>Already registered? Click to Login</a
>
</div>
</div>
Include this method in your component so that password and confirmed password mismatch error can be emitted to your template.
get passwordMatchError() {
return (
this.signupForm.getError('valuesDoNotMatch') &&
this.signupForm.get('confirmPassword')?.touched
);
}
Place the following code under confirm password mat-form-field section so that the mismatch error can be shown.
<mat-error *ngIf="passwordMatchError">Password and confirmed password do not match.</mat-error>

TypeError: Cannot read property 'get' of null - FormControlName

This is my error
core.js:6479 ERROR TypeError: Cannot read property 'get' of null
at FormGroupDirective.addControl (forms.js:5346)
at FormControlName._setUpControl (forms.js:5929)
at FormControlName.ngOnChanges (forms.js:5874)
at FormControlName.rememberChangeHistoryAndInvokeOnChangesHook (core.js:1498)
at callHook (core.js:2536)
at callHooks (core.js:2495)
at executeInitAndCheckHooks (core.js:2446)
at selectIndexInternal (core.js:8447)
at Module.ɵɵadvance (core.js:8430)
at SignInComponent_Template (sign-in.component.html:36)
I don't know why and where am I going wrong.
This is my HTML file
<form (formGroup)="signInForm">
<mat-form-field class="full-width">
<mat-label>Email</mat-label>
<input matInput placeholder="Email" name="email" formControlName="email" [(ngModel)]="email">
</mat-form-field>
<mat-form-field class="full-width">
<mat-label>Password</mat-label>
<input matInput placeholder="Password" name="password" formControlName="pass" [(ngModel)]="pass">
</mat-form-field>
<button
(click)="signIn()"
mat-raised-button
color="primary"
class="login-button">
Sign In
</button>
</form>
<form [formGroup]="signUpForm">
<mat-form-field class="full-width">
<mat-label>Username</mat-label>
<input matInput placeholder="Full name" name="name" formControlName="name" [(ngModel)]="name">
</mat-form-field>
<mat-form-field class="full-width">
<mat-label>E-mail</mat-label>
<input matInput placeholder="Email" name="email" formControlName="email" [(ngModel)]="email">
</mat-form-field>
<mat-form-field class="full-width">
<mat-label>Contact</mat-label>
<input matInput placeholder="Contact" name="contact" formControlName="contact" [(ngModel)]="contact">
</mat-form-field>
<mat-form-field class="full-width">
<mat-label>Address</mat-label>
<input matInput placeholder="Address" name="address" formControlName="address" [(ngModel)]="address">
</mat-form-field>
<mat-form-field class="full-width">
<mat-label>Password</mat-label>
<input matInput placeholder="Password" name="pass" formControlName="pass" [(ngModel)]="pass">
</mat-form-field>
<mat-form-field class="full-width">
<mat-label>Confirm Password</mat-label>
<input matInput placeholder="Confirm Password" name="conpass" formControlName="conpass" [(ngModel)]="conpass">
</mat-form-field>
<!-- <label class="example-margin">Type of User:</label>
<mat-radio-group>
<mat-radio-button class="example-margin" value="after">Buyer</mat-radio-button>
<mat-radio-button class="example-margin" value="before">Seller</mat-radio-button>
</mat-radio-group> -->
<mat-form-field appearance="fill">
<mat-label>Choose one</mat-label>
<mat-select [formControl]="selected" [errorStateMatcher]="matcher" name="option" id="option">
<mat-option value="none">please select</mat-option>
<mat-option value="valid">Buyer</mat-option>
<mat-option value="invalid">Seller</mat-option>
</mat-select>
</mat-form-field>
<button (click)="signUp()"
mat-raised-button
color="primary"
class="login-button">
Sign Up
</button>
</form>
And this is my TS file
import { NumberInput } from '#angular/cdk/coercion';
import { Component, OnInit } from '#angular/core';
import { FormControl, Validators, FormGroupDirective, NgForm, FormGroup, FormBuilder } from '#angular/forms';
import {ErrorStateMatcher} from '#angular/material/core';
export class MyErrorStateMatcher implements ErrorStateMatcher {
isErrorState(control: FormControl | null, form: FormGroupDirective | NgForm | null): boolean {
const isSubmitted = form && form.submitted;
return !!(control && control.invalid && (control.dirty || control.touched || isSubmitted));
}
}
#Component({
selector: 'app-sign-in',
templateUrl: './sign-in.component.html',
styleUrls: ['./sign-in.component.css']
})
export class SignInComponent implements OnInit {
email:String="";
name:String="";
contact:NumberInput="";
address:String="";
pass:String="";
conpass:String="";
constructor( private fb : FormBuilder) { }
signUpForm=this.fb.group ({
name : new FormControl(Validators.required),
email : [null,[Validators.email , Validators.required]],
contact :[null,[Validators.required]],
address : [null,[Validators.required]],
pass : [null,[Validators.required]],
conpass : [null,[Validators.required]]
});
signInForm=this.fb.group({
email : [null,[Validators.email , Validators.required]],
pass : [null,[Validators.required]]
});
selected = new FormControl('valid', [
Validators.required,
Validators.pattern('valid'),
]);
selectFormControl = new FormControl('valid', [
Validators.required,
Validators.pattern('valid'),
]);
nativeSelectFormControl = new FormControl('valid', [
Validators.required,
Validators.pattern('valid'),
]);
matcher = new MyErrorStateMatcher();
// favoriteSeason: string;
// seasons: string[] = ['Winter', 'Spring', 'Summer', 'Autumn'];
// onLogin(form : NgForm)
// {
// console.log(form.value)
// }
// onSingup(form : NgForm)
// {
// console.log(form.value)
// }
ngOnInit(): void {
}
signUp(){
if(this.signUpForm.valid || (this.signUpForm.controls.pass.value != this.signUpForm.controls.conpass.value))
{
console.log("Invalid Form!")
return;
}
console.log(JSON.stringify(this.signUpForm.value))
}
signIn(){
if(this.signUpForm.valid)
{
console.log("Invalid Form!")
return;
}
console.log(JSON.stringify(this.signUpForm.value))
}
}
I thought that not mentioning ngModel would be an issue first but even after adding that the same error again and again, when I run the code it my GUI is totally destroyed and disrupted showing the above error.
Please help me with this, stuck since forever here.
Your signInForm form group directive should be in a square bracket.
(formGroup)="signInForm"
It should be like,
[formGroup]="signInForm"

Custom Validations in Angular FormArray (Sum of proportion must be 100%)

I have created a formArray in angular to represent Nominee's distribution which has two fields Name and Proportion. Plus button(+) adds a new row and (X) button deletes current row. Now I want to code for a validation such that total of proportion column must be 100% (No matter how many nominees' name it consists)
Ex.
No Name Proportion
1 Andy 100
(Sum of proportion is 100)----------
Ex.2
No Name Proportion
1 Andy 60
2 Bruce 40 (Sum of proportion is 100)----------
Ex.3
No Name Proportion
1 Andy 60
2 Bruce 20
3 Ciao 20 (Sum of proportion is 100)----------
Here is my component.html code
<h5>Nominees</h5>
<div class="row">
<form novalidate [formGroup]="FormNominees">
<div clas="col-xs-12 form-group marL40">
<div formGroupName="itemRows">
<ng-container *ngIf="FormNominees.controls.itemRows!=null">
<div *ngFor="let itemrow of FormNominees.controls.itemRows.controls; let i = index"
[formGroupName]="i">
<div class="row">
<mat-form-field
class="example-full-width d-block input-small-size col-sm-2.4"
appearance="outline">
<input matInput placeholder="Name" formControlName="name">
<mat-error *ngIf="f9.name.touched && f9.name.errors?.required">It is mandatory
</mat-error>
<mat-error *ngIf="f9.name.touched && f9.name.errors?.pattern">Can only contain characters.
</mat-error>
</mat-form-field>
<mat-form-field
class="example-full-width d-block input-small-size col-sm-2.4"
appearance="outline">
<input matInput placeholder="Relationship"
formControlName="relationship">
<mat-error *ngIf="f9.relationship.touched && f9.relationship.errors?.required">It is mandatory
</mat-error>
</mat-form-field>
<mat-form-field
class="example-full-width d-block input-small-size col-sm-2.4"
appearance="outline">
<mat-select formControlName="gender" placeholder="Gender">
<mat-option value="Male">Male</mat-option>
<mat-option value="Female">Female</mat-option>
<mat-option value="Other">Other</mat-option>
</mat-select>
<mat-error *ngIf="f9.gender.touched && f9.gender.errors?.required">It is mandatory
</mat-error>
</mat-form-field>
<mat-form-field
class="example-full-width d-block input-small-size col-sm-2.4"
appearance="outline">
<input matInput placeholder="phone" formControlName="phone">
<mat-error *ngIf="f9.phone.touched && f9.phone.errors?.required">It is mandatory
</mat-error>
<mat-error *ngIf="f9.phone.touched && f9.phone.errors?.pattern">Can only contain numbers.
</mat-error>
</mat-form-field>
<mat-form-field
class="example-full-width d-block input-small-size col-sm-2.4"
appearance="outline">
<input matInput placeholder="Proportion"
formControlName="gratuityProportion">
<mat-error *ngIf="f9.gratuityProportion.touched && f9.gratuityProportion.errors?.required">It is mandatory
</mat-error>
<mat-error *ngIf="f9.gratuityProportion.touched && f9.gratuityProportion.errors?.pattern">Can only contain numbers.
</mat-error>
<mat-error *ngIf="f9.gratuityProportion.touched && f9.gratuityProportion.errors?.proportionValidator">Total must be 100%.
</mat-error>
</mat-form-field>
<div class="col-sm-2.4">
<button (click)="deleteRow(i)" class="btn btn-danger">x</button>
<!-- </div>
<div class="form-group"> -->
<button type="button" (click)="addnewRow()"
[disabled]="FormNominees.invalid"
class="btn btn-primary">+</button>
</div>
</div>
</div>
</ng-container>
</div>
</div>
</form>
</div> <br>
Here is my component.ts code
import { proportionValidator } from './proportion.validator';
#Component({
selector: 'app-component',
templateUrl: './component.component.html',
styleUrls: ['./component.component.scss']
})
export class GratuityComponent implements OnInit {
FormNominees: FormGroup;
TotalRow: number;
itemFB: any;
constructor(private fb: FormBuilder) {
}
ngOnInit(): void {
this.FormNominees = this.fb.group({
itemRows: this.fb.array([this.initItemRow()])
});
initItemRow() {
this.itemFB = this.fb.group({
name: ['', [Validators.required, Validators.pattern('[a-zA-Z0-9. ]*' )]],
relationship: ['', Validators.required],
phone: ['', [Validators.required, Validators.pattern('[a-zA-Z0-9. ]*' )]],
gratuityProportion: ['', [Validators.required, Validators.pattern('^[0-9]*$'), proportionValidator] ],
gender:['', Validators.required],
employeeUniqueId: '00000001-0001-0001-0001-000000000001'
})
return this.itemFB;
}
addnewRow() {
const control = <FormArray>this.FormNominees.controls['itemRows'];
control.push(this.initItemRow())
}
deleteRow(index: number) {
const control = <FormArray>this.FormNominees.controls['itemRows'];
// control.push(this.initItemRow())
if (control != null) {
this.TotalRow = control.value.length;
}
if (this.TotalRow > 1) {
control.removeAt(index);
} else {
alert('One record is mandatory');
return false;
}
}
get f9() {return this.itemFB.controls;}
}
}
Now, my question is what code should I write in proportion.validator.ts to achieve the condition?
Straight from the docs:
const arr = new FormArray(
[
new FormControl('Nancy'),
new FormControl('Drew')
],
{
validators: myValidator //<- this is where your proportion validator goes
}
);
In your case, it looks like this:
this.FormNominees = this.fb.group({
itemRows: this.fb.array(
[
this.initItemRow()
],
{
validators: proportionValidator
}
)
});

Angular 6 form returns validation error after submit and reset

I'm using angular 6 and I have a form and a button. When I press the button the app shows the form data above the form and I call form.reset(). But after form reset the input fields become red because I set the fields required in my form. Where is the problem?
app.html
<form [formGroup]='fuelForm'>
<mat-form-field class="input input2">
<input matInput placeholder="Nozzle name" formControlName="nozzleName">
</mat-form-field>
<mat-form-field class="input input2">
<input matInput type="number" min="1" id="nozzleNumber" formControlName="nozzleNumber" placeholder="Nozzle number" >
</mat-form-field>
<mat-form-field class="input input4">
<mat-select placeholder="Fuel type" formControlName="fuelType">
<mat-option *ngFor="let item of fuelList" [value]="item">{{item}}</mat-option>
</mat-select>
</mat-form-field>
<button mat-icon-button class="circle_button" (click)="add()">
<mat-icon class="plus_icon">add_circle_outline</mat-icon>
</button>
</form>
app.ts
export class DialogNozzleComponent {
fuelForm :FormGroup;
fuelList = ['Petrol', 'Super petrol', 'Euro4 petrol', 'Gasoline', 'Euro4 gasoline'];
nozzleItem = [
{
nozzleName: 'Nozzle',
nozzleNumber: '1',
fuelType: 'Super petrol'
},
{
nozzleName: 'Nozzle',
nozzleNumber: '2',
fuelType: 'Gasoline'
}
];
constructor(public fb : FormBuilder) {
this.fuelForm = fb.group({
nozzleName: {value:'Nozzle', disabled: true},
nozzleNumber: [null, Validators.required],
fuelType: [null, Validators.required]
});
}
add() {
const formValue = this.fuelForm.value;
formValue.nozzleName = this.fuelForm.controls['nozzleName'].value;
this.nozzleItem.push(formValue);
this.fuelForm.controls['nozzleNumber'].reset();
this.fuelForm.controls['fuelType'].reset();
}
}
Have you tried
this.fuelForm.reset();
this.fuelForm.markAsPristine();

Form Validation between multiple input fields

So I have a form with multiple input form fields,and a nested form group. In the nested formgroup, the validation should be such that if any one of the three inputs is filled, then the form should be valid. The person can fill either all, or even just one and the form should be valid. My template code is as follows:
<h3 class="form-title">{{title}}</h3>
<form [formGroup]="formX" novalidate>
<div formGroupName="brandIdentifier">
<mat-form-field class="full-width">
<mat-icon matSuffix color="primary" *ngIf="brandName.valid && brandName.touched">done</mat-icon>
<mat-icon matSuffix color="primary" *ngIf="brandName.invalid && brandName.touched">close</mat-icon>
<input matInput type="text" placeholder="Brand Name" formControlName="brandName" />
</mat-form-field>
<mat-form-field class="full-width">
<mat-icon matSuffix color="primary" *ngIf="brandId.valid && brandId.touched">done</mat-icon>
<mat-icon matSuffix color="primary" *ngIf="brandId.invalid && brandId.touched">close</mat-icon>
<input matInput type="text" placeholder="Brand Id" formControlName="brandId" />
</mat-form-field>
<mat-form-field class="full-width">
<mat-icon matSuffix color="primary" *ngIf="contentId.valid && contentId.touched">done</mat-icon>
<mat-icon matSuffix color="primary" *ngIf="contentId.invalid && contentId.touched">close</mat-icon>
<input matInput type="text" placeholder="Content Id" formControlName="contentId" />
</mat-form-field>
</div>
<mat-form-field class="full-width">
<mat-icon matSuffix color="primary" *ngIf="startTime.valid && startTime.touched">done</mat-icon>
<mat-icon matSuffix color="primary" *ngIf="startTime.invalid && startTime.touched">close</mat-icon>
<input matInput type="text" placeholder="Start Time" formControlName="startTime" />
</mat-form-field>
<mat-form-field class="full-width">
<mat-icon matSuffix color="primary" *ngIf="endTime.valid && endTime.touched">done</mat-icon>
<mat-icon matSuffix color="primary" *ngIf="endTime.invalid && endTime.touched">close</mat-icon>
<input matInput type="text" placeholder="End Time" formControlName="endTime" />
</mat-form-field>
<button mat-raised-button color="primary" (click)="startAnalysis()" [ngClass]="{'form-valid':formX.valid, 'form-invalid':formX.invalid}">Submit</button>
<pre>{{formX.value | json}}</pre>
</form>
How would I go about this? using Validator class is a given, but I'm unable to get it optional.
You can use a custom validator for this, apply the custom validator for the nested group, where we check that at least one of the three fields has a value else than empty string, so here's a sample:
Build form:
this.myForm = this.fb.group({
nestedGroup: this.fb.group({
first: [''],
second: [''],
third: ['']
// apply custom validator for the nested group only
}, {validator: this.myCustomValidator})
});
Custom validator:
myCustomValidator(group: FormGroup) {
// if true, all fields are empty
let bool = Object.keys(group.value).every(x => group.value[x] === '')
if(bool) {
// return validation error
return { allEmpty: true}
}
// valid
return null;
}
Then in your form you can show the validation message by:
<small *ngIf="myForm.hasError('allEmpty','nestedGroup')">
Please fill at least one field
</small>
Finally a DEMO :)
Please follow below steps:
Note: we are just giving idea how you can solve your problem.
import FormsModule, ReactiveFormsModule in module.ts
import { FormsModule, ReactiveFormsModule } from '#angular/forms';
#NgModule({
imports: [FormsModule, ReactiveFormsModule]})
Modify your html as given e.g.
User name
User name is required.
User name must be at least 4 characters long.
Password
Password is required.
Password must be at least 6 characters long.
Forget the password ?
<div class="form-group">
<button type="submit" (click)='onSubmit()' dir-btn-click [disabled]="!loginForm.valid" class="btn btn-inverse btn-block">Sign in</button>
</div>
</form>
Modify code as below in [yourcomponent].ts e.g.:
import { Component } from '#angular/core';
import { FormBuilder, FormGroup, Validators } from '#angular/forms';
#Component({
selector: 'app-login',
templateUrl: './login.component.html',
styleUrls: ['./login.component.css']
})
export class LoginComponent {
loginForm: FormGroup;
constructor( private fb: FormBuilder) {
this.crateLoginForm()
}
get userName() { return this.loginForm.get('userName'); }
get password() { return this.loginForm.get('password'); }
crateLoginForm() {
this.loginForm = this.fb.group({
userName: ['', [Validators.required, Validators.minLength(4)]],
password: ['', [Validators.required, Validators.minLength(6)]]
})
}
onSubmit() {
let userName= this.loginForm.value.userName;
let pwd =this.loginForm.value.password;
}
}

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