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I´m fairly new to Angular2 and I have a little problem:
In my Login-Component-HTML, I have two checkboxes, which I want to bind in two way data-binding to the Login-Component-TypeScript.
This is the HTML:
<div class="checkbox">
<label>
<input #saveUsername [(ngModel)]="saveUsername.selected" type="checkbox" data-toggle="toggle">Save username
</label>
And this is the Component.ts:
import { Component, OnInit } from '@angular/core';
import { Router } from '@angular/router';
import { Variables } from '../../services/variables';
@Component({
selector: 'login',
moduleId: module.id,
templateUrl: 'login.component.html',
styleUrls: ['login.component.css']
export class LoginComponent implements OnInit {
private saveUsername: boolean = true;
private autoLogin: boolean = true;
constructor(private router: Router, private variables: Variables) { }
ngOnInit() {
this.loginValid = false;
// Get user name from local storage if you want to save
if (window.localStorage.getItem("username") === null) {
this.saveUsername = true;
this.autoLogin = true;
console.log(this.saveUsername, this.autoLogin);
} else {
console.log("init", window.localStorage.getItem("username"));
login(username: string, password: string, saveUsername: boolean, autoLogin: boolean) {
this.variables.setUsername(username);
this.variables.setPassword(password);
this.variables.setIsLoggedIn(true);
console.log(saveUsername, autoLogin);
//this.router.navigate(['dashboard']);
If I click an checkbox, I get the correct value in the controller (component).
But if I change the value of for example saveUsername in the component, the checkbox didn't "get" the new value.
So I can´t manipulate the checkbox from the Component (like I want to do in the ngOnInit in the component.
Thanks for your help!
You can remove .selected from saveUsername in your checkbox input since saveUsername is a boolean. Instead of [(ngModel)] use [checked]="saveUsername" (change)="saveUsername = !saveUsername"
Edit: Correct Solution:
<input
type="checkbox"
[checked]="saveUsername"
(change)="saveUsername = !saveUsername"/>
Update: Like @newman noticed when ngModel is used in a form it won't work. However, you should use [ngModelOptions] attribute like (tested in Angular 7):
<input
type="checkbox"
[(ngModel)]="saveUsername"
[ngModelOptions]="{standalone: true}"/> `
I also created an example at Stackblitz: https://stackblitz.com/edit/angular-abelrm
–
–
–
–
Unfortunately solution provided by @hakani is not two-way binding. It just handles One-way changing model from UI/FrontEnd part.
Instead the simple:
<input [(ngModel)]="checkboxFlag" type="checkbox"/>
will do two-way binding for checkbox.
Afterwards, when Model checkboxFlag is changed from Backend or UI part - voila, checkboxFlag stores actual checkbox state.
To be sure I've prepared Plunker code to present the result : https://plnkr.co/edit/OdEAPWRoqaj0T6Yp0Mfk
Just to complete this answer you should include the import { FormsModule } from '@angular/forms' into app.module.ts and add to imports array i.e
import { FormsModule } from '@angular/forms';
[...]
@NgModule({
imports: [
[...]
FormsModule
[...]
–
–
–
type="checkbox"
[checked]="saveUsername"
(change)="onSaveUsernameChanged(saveUserNameCheckBox.checked)" />
component.ts
public saveUsername:boolean;
public onSaveUsernameChanged(value:boolean){
this.saveUsername = value;
I'm working with Angular5 and I had to add the "name" attribute to get the binding to work... The "id" is not required for binding.
<input type="checkbox" id="rememberMe" name="rememberMe" [(ngModel)]="rememberMe">
–
.html file
<input [(ngModel)]="userConsent" id="userConsent" required type="checkbox"/> " I Accept"
.ts file
userConsent: boolean = false;
import FormsModule in your module
Put the input inside a form tag
your input should be like this:
<input name="mpf" type="checkbox" [(ngModel)]="value" />
Note: do not forget to put name in your input.
this._model = checked;
this.checked.emit(this._model);
console.log('@Input(setmodel'+checked);
get model() {
return this._model;
strange thing is this works
<mycheckbox [checked]="isChecked" (checked)="isChecked = $event">
while this wont
<mycheckbox [(checked)]="isChecked">
<div class="checkbox">
<label>
<input name="selected" [(ngModel)]="saveUsername.selected" type="checkbox">Save username
</label>
I know it may be repeated answer
but for any one want to load list of checkboxes with selectall checkbox into angular form i follow this example:
Select all/deselect all checkbox using angular 2+
it work fine but just need to add
[ngModelOptions]="{standalone: true}"
the final HTML should be like this:
<li><input type="checkbox" [(ngModel)]="selectedAll" (change)="selectAll();"/></li>
<li *ngFor="let n of names">
<input type="checkbox" [(ngModel)]="n.selected" (change)="checkIfAllSelected();">{{n.name}}
TypeScript
selectAll() {
for (var i = 0; i < this.names.length; i++) {
this.names[i].selected = this.selectedAll;
checkIfAllSelected() {
this.selectedAll = this.names.every(function(item:any) {
return item.selected == true;
hope this help
In any situation, if you have to bind a value with a checkbox which is not boolean then you can try the below options
In the Html file:
<div class="checkbox">
<label for="favorite-animal">Without boolean Value</label>
<input type="checkbox" value="" [checked]="ischeckedWithOutBoolean == 'Y'"
(change)="ischeckedWithOutBoolean = $event.target.checked ? 'Y': 'N'">
in the componentischeckedWithOutBoolean: any = 'Y';
See in the stackblitz
https://stackblitz.com/edit/angular-5szclb?embed=1&file=src/app/app.component.html
@Input() trueValue:any;
@Input() falseValue:any;
@Output() checkModelChange = new EventEmitter<any>();
constructor(private el: ElementRef) { }
ngOnInit() {
this.el.nativeElement.checked = this.checkModel==this.trueValue;
@HostListener('change', ['$event']) onChange(event:any) {
this.checkModel = event.target.checked ? this.trueValue : this.falseValue;
this.checkModelChange.emit(this.checkModel);
<input type="checkbox" [(checkModel)]="check" [trueValue]="1" [falseValue]="0">
–
<p-checkbox name="checkbox" value="isAC"
label="All Colors" [(ngModel)]="selectedAllColors"
[ngModelOptions]="{standalone: true}" id="al"
binary="true">
</p-checkbox>
And more importantly, don't forget to include [ngModelOptions]="{standalone: true} as well as it SAVED MY DAY.
A workaround to achieve the same specially if you want to use checkbox with for loop is to store the state of the checkbox inside an array and change it based on the index of the *ngFor loop. This way you can change the state of the checkbox in your component.
app.component.html
<div *ngFor="let item of items; index as i">
<input type="checkbox" [checked]="category[i]" (change)="checkChange(i)">
{{item.name}}
app.component.ts
items = [
{'name':'salad'},
{'name':'juice'},
{'name':'dessert'},
{'name':'combo'}
category= []
checkChange(i){
if (this.category[i]){
this.category[i] = !this.category[i];
else{
this.category[i] = true;
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