The event property accessors use the predefined key for the event property to add and remove instances from the delegate collection.

事件属性访问器使用事件属性的预定义键在委托集合中添加和从委托集合中移除实例。

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The event property accessors use the predefined key for the event property to add and remove instances from the delegate collection.

事件属性访问器使用事件属性的预定义键在委托集合中添加和从委托集合中移除实例。

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