angularjs – 当ng-pattern为$invalid时,Angular.js – ng-chang

我使用ng-pattern来验证一些表单字段，我使用ng-change来观察和处理任何更改，但是ng-change(或$ scope。$ watch)只会在表单元素位于$ valid state！我是新的角，所以我不知道如何解决这个问题，虽然我怀疑一个新的指令是要走的路。

如何获得ng-change在$ invalid和$ valid表单元素状态中触发，ng-pattern仍然像以前一样设置表单元素的状态？

Html：

<div ng-app="test">
  <div ng-controller="controller">
    <form name="form">
        <input type="text" name="textbox" ng-pattern="/^[0-9]+$/" ng-change="change()" ng-model="inputtext"> Changes: {{ changes }}
    </form>

    <br>
    Type in any amount of numbers,and changes should increment.

    <br><br>
    Now enter anything that isn't a number,and changes will stop incrementing. When the form is in the $invalid state,ng-change doesn't fire.

    <br><br>
    Now remove all characters that aren't numbers. It will increment like normal again. When the form is in the $valid state,ng-change will fire.

    <br><br>
    I would like ng-change to fire even when the the form is $invalid.

    <br><br>
        form.$valid: <font color="red">{{ form.$valid }}</font>

  </div>
</div>

Javascript：

angular.module('test',[]).controller('controller',function ($scope) {
    $scope.changes = 0;
    $scope.change = function () {
        $scope.changes += 1;
    };
});

我创建了一个工作的JS小提琴，它显示了我有的问题。

http://jsfiddle.net/JAN3x/1/

顺便说一下，这个角度问题似乎也是相关的：
https://github.com/angular/angular.js/issues/1296

<input type="text" name="textbox" ng-pattern="/^[0-9]+$/" watch-change="change()" ng-model="inputtext"> Changes: {{ changes }}

app.directive('watchChange',function() {
    return {
        scope: {
            onchange: '&watchChange'
        },link: function(scope,element,attrs) {
            element.on('input',function() {
                scope.$apply(function () {
                    scope.onchange();
                });
            });
        }
    };
});