Can I programmatically apply Angular validation directives inside a custom directive?

Question

I have found great many occurrences of the following pattern for html inputs, this being for phone numbers:

Answer 1

If you're using more validations, you can create a service that is responsible for identifying and validating the elements, without any limitation. Default directives of angular remain.

Example:

    module.service('$Validation', ["$compile",function($compile){

        this.validators = {
            'phoneNumber': [['required', 1], ['minlength',6], ['maxlength', 10], ['pattern', /^[0-9]+$/.source]],
            'phoneNumber2Custom': function(value){ 
                return /^[0-9]{6,10}$/.test(value) 
            },
            'userTwitter': function(value){
                return /^@(.+)/.test(value)
            }
            // ...etc... /
        }

        this.add = function(scope, element, attrs, model){
            var name = attrs.bkNgValidation, type;
            if(!(type = this.validators[name])) return;
            else if(angular.isFunction(type)) return (model.$validators[name] = type);

            element.removeAttr("bk-ng-validation");
            angular.forEach(type, function(expr){
                element.attr(expr[0], expr[1])
            });
            $compile(element)(scope)        
        };

    }]).directive('bkNgValidation', ["$Validation", function ($Validation) {
        return {
            require: '?ngModel',
            priority: 1e5,
            link: function(){
                $Validation.add.apply($Validation, arguments);
            }
        }
    }])

Demo