Recently, I created a custom directive inspired by a solution on Stack Overflow that restricts user input to only digits:
.directive('onlydigitinput', function () {
return {
require: 'ngModel',
link: function (scope, element, attrs, modelCtrl) {
modelCtrl.$parsers.push(function (inputValue) {
var transformedInput = inputValue.toLowerCase().replace(/ /g, '')
.replace(/[^0-9]+/g, '');
if (transformedInput != inputValue) {
modelCtrl.$setViewValue(transformedInput);
modelCtrl.$render();
}
return transformedInput;
});
}
};
})
Initially, the directive worked perfectly. However, when I combined it with the 'required' directive, issues started to arise.
The HTML snippet I used was:
input(type='text' , required, onlydigitinput, min='1', max='99', maxlength='2')
I avoided using type='number' due to a bug in Chrome that disregarded the maxlength attribute and interfered with my directive. Everything works fine when entering digits, but the problem occurs when starting with a non-digit character. In this case, I receive the following error message:
TypeError: Cannot read property 'toLowerCase' of undefined
at http://localhost:3000/scripts/core/directives/systemDirectives.js:63:54
This error seems to be caused by the toLowerCase function in my directive. I am seeking advice on how to resolve this error and enhance the performance of my directive to handle such scenarios effectively.