Question

Emberjs如何在Javascript中完成以下语法？

var handler = function(){
   console.log('Triggered');
}.on('someEvent');

感兴趣的部分是.on('whatever')。当我尝试在Ember之外使用这种语法时，我会收到错误。

谢谢！

Answer 1

他们是这样做的：

  /**
    The `on` extension of Javascript's Function prototype is available
    when `Ember.EXTEND_PROTOTYPES` or `Ember.EXTEND_PROTOTYPES.Function` is
    true, which is the default.

    You can listen for events simply by adding the `on` call to the end of
    your method declarations in classes or mixins that you write. For example:

    ```javascript
    Ember.Mixin.create({
      doSomethingWithElement: function() {
        // Executes whenever the "didInsertElement" event fires
      }.on('didInsertElement')
    });
    ```

    See `Ember.on`.

    @method on
    @for Function
  */
  Function.prototype.on = function() {
    var events = a_slice.call(arguments);
    this.__ember_listens__ = events;
    return this;
  };
}

http://builds.emberjs.com/release/ember.js

Emberjs如何看似扩展Javascript的语法？

1 个答案: