BindingsCollection.OnCollectionChanging(CollectionChangeEventArgs) BindingsCollection.OnCollectionChanging(CollectionChangeEventArgs) BindingsCollection.OnCollectionChanging(CollectionChangeEventArgs) BindingsCollection.OnCollectionChanging(CollectionChangeEventArgs) Method

定义

引发 CollectionChanging 事件。Raises the CollectionChanging event.

protected:
 virtual void OnCollectionChanging(System::ComponentModel::CollectionChangeEventArgs ^ e);
protected virtual void OnCollectionChanging (System.ComponentModel.CollectionChangeEventArgs e);
abstract member OnCollectionChanging : System.ComponentModel.CollectionChangeEventArgs -> unit
override this.OnCollectionChanging : System.ComponentModel.CollectionChangeEventArgs -> unit
Protected Overridable Sub OnCollectionChanging (e As CollectionChangeEventArgs)

参数

注解

事件发生时将发生事件。CollectionChangingThe CollectionChanging event occurs when the event is about to change.

引发事件时,将通过委托调用事件处理程序。Raising an event invokes the event handler through a delegate. 有关详细信息, 请参阅处理和引发事件For more information, see Handling and Raising Events.

OnCollectionChanging 方法还允许派生类对事件进行处理而不必附加委托。The OnCollectionChanging method also allows derived classes to handle the event without attaching a delegate. 这是在派生类中处理事件的首选技术。This is the preferred technique for handling the event in a derived class.

继承者说明

在派生类中重写 OnCollectionChanging(CollectionChangeEventArgs) 时,一定要调用基类的 OnCollectionChanging(CollectionChangeEventArgs) 方法,以便已注册的委托对事件进行接收。When overriding OnCollectionChanging(CollectionChangeEventArgs) in a derived class, be sure to call the base class's OnCollectionChanging(CollectionChangeEventArgs) method so that registered delegates receive the event.

适用于