Restrict input as numbers on input fields using AngularJS - angularjs

Question

I am trying to restrict input as numbers on below fields
Postal Code:
<input type="text" id="zipCode1" name="zipCode1" size="4" maxlength="5" ng-model="zipCode1" ng-change="myNumbers(zipCode1)" />
<input type="text" id="zipCode2" name="zipCode2" size="3" maxlength="4" ng-model="zipCode2" ng-change="myNumbers(zipCode2)" />
it doesn't work with
$scope.myNumbers = function(fieldName){
var tN = fieldName.replace(/[^\d]/g, "");
if(tN != fieldName)
fieldName = tN
};
It works with below code but changing both the fields
$scope.$watch('myNumbers', function() {
var tN = $scope.myNumbers.replace(/[^\d]/g, "");
if(tN != $scope.myNumbers)
$scope.myNumbers = tN;
})
Need to change the value for the input field where user is typing and not both

Answer 1

Use the directive found here: https://stackoverflow.com/a/19675023/149060 instead of the ng-change function. Replicated here for easy reference:
angular.module('app').
directive('onlyDigits', function () {
return {
restrict: 'A',
require: '?ngModel',
link: function (scope, element, attrs, ngModel) {
if (!ngModel) return;
ngModel.$parsers.unshift(function (inputValue) {
var digits = inputValue.split('').filter(function (s) { return (!isNaN(s) && s != ' '); }).join('');
ngModel.$viewValue = digits;
ngModel.$render();
return digits;
});
}
};
});

Answer 2

You could try adding to the inputs ng-pattern='/^\d{2}$/'

Answer 3

Here is a directive I've done to restrict the keys allowed.
angular.module('app').directive('restrictTo', function() {
return {
restrict: 'A',
link: function (scope, element, attrs) {
var re = RegExp(attrs.restrictTo);
var exclude = /Backspace|Enter|Tab|Delete|Del|ArrowUp|Up|ArrowDown|Down|ArrowLeft|Left|ArrowRight|Right/;
element[0].addEventListener('keydown', function(event) {
if (!exclude.test(event.key) && !re.test(event.key)) {
event.preventDefault();
}
});
}
}
});
And the input would look like:
<input type="text" name="zipCode1" maxlength="5" ng-model="zipCode1" restrict-to="[0-9]">
The regular expression evaluates the pressed key, not the value.
It also works perfectly with inputs type="number" because prevents from changing its value, so the key is never displayed and it does not mess with the model.