javascript – Angular Directive绑定函数带有&不传递参数给控制器

一旦用户选择文件/文件夹,Box文件选择器就可以设置回调函数,如下所示：

var boxSELEct = new BoxSELEct();
// Register a success callBACk handler
boxSELEct.success(function(responsE) {
    console.log(responsE);
});

我的控制器正在使用该指令,并且将成功的回调逻辑作为范围变量,我正在传递给该指令.

我创建了一个plunkr,我在嘲笑Box选择行为

调节器

.controller('myController',function($scopE) {
  $scope.onsuccessful = function(messagE) {
    alert('success! message: ' + messagE);
  };
})

指示

angular.module('myApp',[])
  .controller('myController',function($scopE) {
    $scope.onsuccessful = function(messagE) {
      //message is undefined here
      alert('success! message: ' + messagE);
    };
  })
  .directive('myDirective',function() {
    return {
      reStrict: 'A',scope: {
        success: '&'
      },link: function(scope,element) {

        //third party allows to subscribe to success and failure functions
        function ThirdPartySELEct() {

        }

        ThirdPartySELEct.prototype.success = function(callBACk) {
          this.callBACk = callBACk;

        };

        ThirdPartySELEct.prototype.firesuccess = function() {
          this.callBACk({
            foo: 'bar'
          });
        };

        var myThirdPartyInstance = new ThirdPartySELEct();
        myThirdPartyInstance.success(function(messagE) {
          //message is still defined here,but not in the controller
          scope.success(messagE);
        });

        element.on('click',function() {
          myThirdPartyInstance.firesuccess();
        });

      }
    };
  });

视图

<div ng-controller="myController">
  <button my-directive success="onsuccessful(arg)">Test</button>
</div>

回调函数在控制器内调用,但是参数
未定义

我使用’=’而不是’&’来解决这个问题,但我想知道为什么它不能与’&’因为它应该用于method binding