AngularJS ng-model Directive


The ng-model directive binds the value of HTML controls (input, select, textarea) to application data.

* The ng-model Directive

With the ng-model directive, you can bind the value of an input field to a variable created in AngularJS.

Example:

<div ng-app="myapp" ng-controller="myctrl">
    Name: <input ng-model="name">
</div>

<script>
var app = angular.module('myapp', []);
app.controller('myctrl', function($scope) {
    $scope.name = "Dhaval";
});
</script>


* Two-Way Binding

The binding goes both ways. If the user changes the value inside the input field, the AngularJS property will also change its value:

Example: 

<div ng-app="myapp" ng-controller="myctrl">
    Name: <input ng-model="name">
    <h1>You entered: {{name}}</h1>
</div>


* Validate User Input


The ng-model directive can provide type validation for application data (number, e-mail, required):

Example:

<form ng-app="" name="myForm">
    Email:
    <input type="email" name="myAddress" ng-model="text">
    <span ng-show="myForm.myAddress.$error.email">Not a valid e-mail address</span>
</form>

In the example above, the span will be displayed only if the expression in the ng-show attribute returns true.


* Application Status


The ng-model directive can provide status for application data (valid, dirty, touched, error):

Example:

<form ng-app="" name="myForm" ng-init="myText = 'post@dp.com'">
    Email:
    <input type="email" name="myAddress" ng-model="myText" required>
    <h1>Status</h1>
    {{myForm.myAddress.$valid}}
    {{myForm.myAddress.$dirty}}
    {{myForm.myAddress.$touched}}
</form> 


* CSS Classes


The ng-model directive provides CSS classes for HTML elements, depending on their status:

Example:

<style>
input.ng-invalid {
    background-color: lightblue;
}
</style>
<body>

<form ng-app="" name="myForm">
    Enter your name:
    <input name="myName" ng-model="myText" required>
</form>


The ng-model directive adds/removes the following classes, according to the status of the form field:

  • ng-empty
  • ng-not-empty
  • ng-touched
  • ng-untouched
  • ng-valid
  • ng-invalid
  • ng-dirty
  • ng-pending
  • ng-pristine
Note: If the property in the ng-model attribute does not exist, AngularJS will create one for you.