How to Reset an Input Value when Limit Exceeds using AngularJS ?
The task is to handle an input field if the number entered by the user in the input exceeds some limit using angularJS. We define a limitTo directive and use it on an HTML input element. This directive is used for all the handling of overflowing limits. The directive calls a function on the keypress event where we can check for the limits.
Example 1: This example sets the value of user input to 0 if its limit exceeds to 100.
<!DOCTYPE html><html ng-app="myApp"> <head> <script src= </script></head> <body ng-controller="MyController"> <center> <h1 style="color: green;"> GeeksforGeeks </h1> <b> Edit an input value when it exceeds the limit </b> <br><br> <!-- Custom directive limit-to --> <input limit-to="100" type="number" ng-model="val"> {{val}} </center> <script type="text/javascript"> angular.module('myApp', []) .controller('MyController', ['$scope', function($scope) { // Value to ng model the input $scope.val; }]) .directive("limitTo", ['$timeout', function($timeout) { // Declaration of custom directive return { restrict: "A", link: function(scope, elem, attrs) { var limit = parseInt(attrs.limitTo); elem.on("keypress", function(e) { $timeout(function() { if (parseInt(e.target.value) > limit) { // Handle change here scope.val = 0; scope.$apply(); e.preventDefault(); } }); }); } } }]); </script></body> </html> |
Output: As soon as the user exceeds 100, the value is set back to 0.
Example 2: Here we change the text based on input limit. If the value of input is less than 0 then it goes to 0. If it’s value is greater than 100 then it goes to 100 otherwise it stays as it is.
<!DOCTYPE html><html ng-app="myApp"> <head> <script src= </script></head> <body ng-controller="MyController"> <center> <h1 style="color: green;"> GeeksforGeeks </h1> <b> Edit an input value when it exceeds the limit </b> <br><br> <!-- Custom directive limit-to --> <input limit-to="100" type="number" ng-model="val"> <br> {{text}} </center> <script type="text/javascript"> angular.module('myApp', []) .controller('MyController', ['$scope', function($scope) { // Value to ng model the input $scope.val; $scope.text = 'Inside Limit'; }]) .directive("limitTo", ['$timeout', function($timeout) { // Declaration of custom directive return { restrict: "A", link: function(scope, elem, attrs) { var limit = parseInt(attrs.limitTo); elem.on("keypress", function(e) { $timeout(function() { if (parseInt(e.target.value) > limit) { // Handle change here if greater scope.text = "Outside limit (greater)"; scope.val = 100; scope.$apply(); e.preventDefault(); } else if (parseInt(e.target.value) < 0) { scope.text = "Outside limit (smaller)"; scope.val = 0 scope.$apply(); e.preventDefault(); } else { scope.text = "Inside Limit"; scope.$apply(); e.preventDefault(); } }); }); } } }]); </script></body> </html> |
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