I have 3 <input type="radio" name="radioBtn"> one for each value "none", "true" and "false". Is there a easy ways to bind the value of the selected radio Button to the value of a TextInput, without the use of onChange Events or binding them to variables in my dart script?
Something like:
<input type="text" value="{{radioBtn.value}}"/>
Related
I am using Angular 10. I have a checkbox in my html file. In my typescript file I want to see if the checkbox is checked or not and perform some action accordingly. Is there a way to get the checked state of the checkbox like true if it is checked and false otherwise? TIA.
You can use change event to check the state
<input type="checkbox" (change)="onSelect($event.target.checked)">
onSelect(state:boolean) {
console.log("Is Checked? ", state)
}
If you are not using Template Form or Reactive Form,
<input type="checkbox" (change)="changeEvent($event.target.checked)">
For Template Forms,
<input type="checkbox" [(ngModel)]='checked' (ngModelChange)="changeEvent()">
For reactive forms,
<input type="checkbox" formControlName='check'>
this.form.get('check').valueChanges
.subscribe((check)=> this.changeEvent())
To my knowledge, we have two ways of checking the state of the checkbox:
Use the library for angular, Ex: Material UI: https://material.angular.io/components/checkbox/examples or different libraries.
Use two-way binding of angular [(ngModel)] ="checked" on the HTML template
you can use two-way binding like this
html
<input type="checkbox" [(ngModel)]="checked">
ts
checked = false;
I am trying to assign to a radio button the default value read from the database through a ScaLa parameter, I cannot use an IF loop inside the tag. Any idea?
<input type="checkbox" name="emailConsent" id="emailConsent" class="checkbox" #if(sessionData.user.receiveNews = true ) {checked}>
I have the error "reassignment to val" when I try to compile
I am trying to create a radio button input in my Angular2 app using ngModel and value. I want three options: true, false, and null, but I can't figure out how to set one of the inputs to a value of null. Essentially if nothing has been selected (ie the ngModel value is null) I want that null radio button to be selected. Is there a way to do this easily in the HTML?
Thanks.
Use binding [value]="null"
<input type="radio" id="rb-id" name="rb-name" [(ngModel)]="someVar" [value]="null">
I have an <input>, showing a number. I used ng-model to bind this number to a variable. My problem is that I don't want the variable to change simply on input, I want it to change on button click, but I also want a default value shown in the input to be the one that's stored in the variable.
To make it slightly clearer:
<input type="number" ng-model="foo">
<button ng-click="updateFoo()">Update foo</button>
{{foo}}
I want foo to reflect changes only when button is pressed, but if I refresh the page, {{foo}} will show some value (logic to retrieve the values exist).
The way I currently did it, in my AngularJS controller:
$scope.foo = 5;
$scope.updateFoo = function(num){
$scope.foo = num;
}
and HTML:
<input type="number" ng-model="not_in_controller">
<button ng-click="updateFoo(not_in_controller)">Update foo</button>
{{foo}}
This works as I want it to, but the input is empty by default.
Another thought was to use two variables, one is for presentation, another one is set after clicking the button
Simply use ng-init directive:
<input type="number" ng-model="not_in_controller" ng-init="not_in_controller=5">
<button ng-click="updateFoo(not_in_controller)">Update foo</button>
{{not_in_controller}}
Just use value="{{ foo }}" in your <input />
Here a jsfiddle: http://jsfiddle.net/5s3cjyuw/
I'm really new to HTML, but I can't find anywhere how to return the variable from a check box. I've figured out how to get variables from forms and inputs, but I don't know how to get them from check boxes. Basically, I want a check box that if checked, will return the value yes. If not checked, it doesn't have to return a value, but no would be nice.
When submitting a form, if a checkbox is checked, it will be included in the values collection submitted to the server. If not checked, it will be omitted (as if that checkbox did not exist).
In JavaScript, you can find out whether the checkbox is checked by the checked property:
//returns true or false
var isChecked = document.getElementById('id_of_checkbox').checked;
In ASP.NET, the CheckBox control has a boolean property Checked.
Assign something to the value attribute. You should get the value of the checked box, if there is one in the form values on postback. Note that I've made it a radio input in the case where you want yes or no. For a radio you need to assign the same name, but different ids (if you assign an id at all). You'd want to use checkboxes in the case where you can have more than one value selected or only care to get the value when selected. These types of checkboxes should have different names.
<input type="radio" id="radio_yes" name="radio_btn" value="Yes" /> Yes
<input type="radio" id="radio_no" name="radio_btn" value="No"
checked="checked" /> No
If you only want a single check box with the value yes to be returned if checked, then you can use a check box. You won't get any value if it isn't checked.
<input type="checkbox" id="chk_box" name="chk_box"
value="Yes" /> Do you want this?
On the server-side, you look for the value corresponding to the "radio_btn" (first example) or "chk_box" (second example) key in your form parameters.
Use the 'checked' property.
var checkbox = document.getElementById('checkboxId');
var checked = checkbox.checked;
look at the value of YourCheckboxName.Checked
If a checkbox is disabled, it will be omitted in the values collection submitted to the server even if it is checked:
<input type="checkbox" name="checkbox1">
<input type="checkbox" name="checkbox2" checked>
<input type="checkbox" name="checkbox3" disabled>
<input type="checkbox" name="checkbox4" disabled checked>
Looks like:
result of HTML sample code
Only checkbox2 is in the values collection submitted to the server, if the user submits the form without any changes.