ContentElement.PreviewTextInput 事件
定义
在此元素以设备无关模式获取文本时发生。Occurs when this element gets text in a device-independent manner.
public:
virtual event System::Windows::Input::TextCompositionEventHandler ^ PreviewTextInput;public event System.Windows.Input.TextCompositionEventHandler PreviewTextInput;member this.PreviewTextInput : System.Windows.Input.TextCompositionEventHandler Public Custom Event PreviewTextInput As TextCompositionEventHandler 事件类型
实现
注解
PreviewTextInput事件允许组件或应用程序以与设备无关的方式侦听文本输入。The PreviewTextInput event allows a component or application to listen for text input in a device-independent manner. 键盘是的主要方式 PreviewTextInput ，但语音、手写和其他输入设备也可能会生成 PreviewTextInput 。The keyboard is the primary means of PreviewTextInput; but speech, handwriting, and other input devices can also generate PreviewTextInput.
由于键组合（在默认键盘或通过输入法编辑器）中，多个键事件可能只引发一个文本输入事件。Because of key combinations - either in default keyboards or through input method editors - multiple key events may raise just one text input event.
此事件将为 TextCompositionManager.PreviewTextInput 此类创建附加事件的别名，因此 PreviewTextInput 当 ContentElement 继承为基元素时，它是类成员列表的一部分。This event creates an alias for the TextCompositionManager.PreviewTextInput attached event for this class, so that PreviewTextInput is part of the class members list when ContentElement is inherited as a base element. 附加到事件的事件处理程序 PreviewTextInput 附加到基础 TextCompositionManager.PreviewTextInput 附加事件，并接收相同的事件数据实例。Event handlers that are attached to the PreviewTextInput event are attached to the underlying TextCompositionManager.PreviewTextInput attached event and receive the same event data instance.
路由事件信息Routed Event Information
| 标识符字段Identifier field | PreviewTextInputEvent |
| 路由策略Routing strategy | 隧道Tunneling |
| 委托Delegate | TextCompositionEventHandler |
对应的冒泡事件为 TextInput 。The corresponding bubbling event is TextInput.
重写 OnPreviewTextInput 以在派生类中实现此事件的类处理。Override OnPreviewTextInput to implement class handling for this event in derived classes.