AngularJS enriches form filling and validation. We can use ng-click event to handle the click button and use $dirty and $invalid flags to do the validation in a seamless way. Use novalidate with a form declaration to disable any browser-specific validation. The form controls make heavy use of AngularJS events. Let us have a look at the events first.
AngularJS provides multiple events associated with the HTML controls. For example, ng-click directive is generally associated with a button. AngularJS supports the following events −
Reset data of a form using on-click directive of a button.
<input name = "firstname" type = "text" ng-model = "firstName" required> <input name = "lastname" type = "text" ng-model = "lastName" required> <input name = "email" type = "email" ng-model = "email" required> <button ng-click = "reset()">Reset</button> <script> function studentController($scope) { $scope.reset = function() { $scope.firstName = "Mahesh"; $scope.lastName = "Parashar"; $scope.email = "MaheshParashar@howcodex.com"; } $scope.reset(); } </script>
The following can be used to track error.
$dirty − states that value has been changed.
$invalid − states that value entered is invalid.
$error − states the exact error.
The following example will showcase all the above-mentioned directives.
<html> <head> <title>Angular JS Forms</title> <script src = "https://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script> <style> table, th , td { border: 1px solid grey; border-collapse: collapse; padding: 5px; } table tr:nth-child(odd) { background-color: #f2f2f2; } table tr:nth-child(even) { background-color: #ffffff; } </style> </head> <body> <h2>AngularJS Sample Application</h2> <div ng-app = "mainApp" ng-controller = "studentController"> <form name = "studentForm" novalidate> <table border = "0"> <tr> <td>Enter first name:</td> <td><input name = "firstname" type = "text" ng-model = "firstName" required> <span style = "color:red" ng-show = "studentForm.firstname.$dirty && studentForm.firstname.$invalid"> <span ng-show = "studentForm.firstname.$error.required">First Name is required.</span> </span> </td> </tr> <tr> <td>Enter last name: </td> <td><input name = "lastname" type = "text" ng-model = "lastName" required> <span style = "color:red" ng-show = "studentForm.lastname.$dirty && studentForm.lastname.$invalid"> <span ng-show = "studentForm.lastname.$error.required">Last Name is required.</span> </span> </td> </tr> <tr> <td>Email: </td><td><input name = "email" type = "email" ng-model = "email" length = "100" required> <span style = "color:red" ng-show = "studentForm.email.$dirty && studentForm.email.$invalid"> <span ng-show = "studentForm.email.$error.required">Email is required.</span> <span ng-show = "studentForm.email.$error.email">Invalid email address.</span> </span> </td> </tr> <tr> <td> <button ng-click = "reset()">Reset</button> </td> <td> <button ng-disabled = "studentForm.firstname.$dirty && studentForm.firstname.$invalid || studentForm.lastname.$dirty && studentForm.lastname.$invalid || studentForm.email.$dirty && studentForm.email.$invalid" ng-click="submit()">Submit</button> </td> </tr> </table> </form> </div> <script> var mainApp = angular.module("mainApp", []); mainApp.controller('studentController', function($scope) { $scope.reset = function() { $scope.firstName = "Mahesh"; $scope.lastName = "Parashar"; $scope.email = "MaheshParashar@howcodex.com"; } $scope.reset(); }); </script> </body> </html>
Open the file testAngularJS.htm in a web browser and see the result.