link: function(scope, element, attrs) {
  scope.$watch('boundProperty', function(newVal) {
    if (newVal !== undefined) {
      // 绑定值已填充，执行相关操作
    }
  });
}

link: function(scope, element, attrs) {
  $timeout(function() {
    // 确保绑定已填充后再执行
  });
}

angular.module('app').directive('myDirective', function() {
  return {
    require: '^parentDirective',
    link: function(scope, element, attrs, parentCtrl) {
      // 确保父控制器已存在
    }
  };
});

angular.module('app').directive('myDirective', function() {
  return {
    scope: {
      boundProperty: '='
    },
    bindToController: true,
    controller: function() {
      // 绑定属性会直接附加到控制器实例
    },
    controllerAs: 'vm',
    link: function(scope, element, attrs) {
      // 通过vm.boundProperty访问
    }
  };
});