What is Angular Validation?
Angular Forms and controls in AngularJS give validation services and inform users of invalid input. AngularJS provides us with different information about a form or its inputs and is applied to a form and inputs.
To track error following terms are used:
- $dirty− states that value has been altered.
- $error− states the exact error.
- $invalid− states that value entered is invalid.
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e.g.
<!DOCTYPE html> <html> <script src= "http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script> <body> <h1>Example of Validation</h1> <form ng-app="myApp" ng-controller="validateCtrl" name="intellipaatForm" novalidate> <p>Username:<br> <input type="text" name="username" ng-model="username" required> <span style="color:red" ng-show="intellipaatForm.username.$dirty && intellipaatForm.username.$invalid"> <span ng-show="intellipaatForm.username.$error.required">Username is required.</span> </span> </p> <p>Email:<br> <input type="email" name="email" ng-model="email" required> <span style="color:red" ng-show="intellipaatForm.email.$dirty && intellipaatForm.email.$invalid"> <span ng-show="intellipaatForm.email.$error.required">Email is required.</span> <span ng-show="intellipaatForm.email.$error.email">Invalid email address.</span> </span> </p> <p> <input type="submit" ng-disabled="intellipaatForm.username.$dirty && intellipaatForm.username.$invalid || intellipaatForm.email.$dirty && intellipaatForm.email.$invalid"> </p> </form> <script> var app = angular.module('myApp', []); app.controller('validateCtrl', function($scope) { $scope.username = 'abc'; $scope.email = 'abc@intellipaat.com'; }); </script> </body> </html>
Output
If you remove the name of the id from the text box it shows the following output: