Control.GotFocus Control.GotFocus Control.GotFocus Control.GotFocus Event

定义

在控件接收焦点时发生。Occurs when the control receives focus.

public:
 event EventHandler ^ GotFocus;
[System.ComponentModel.Browsable(false)]
public event EventHandler GotFocus;
member this.GotFocus : EventHandler 
Public Custom Event GotFocus As EventHandler 
属性

示例

下面的代码示例演示如何将此成员。The following code example demonstrates the use of this member. 在示例中,事件处理程序报告的匹配项GotFocus事件。In the example, an event handler reports on the occurrence of the GotFocus event. 此报告可帮助您了解事件发生的并可以帮助您进行调试。This report helps you to learn when the event occurs and can assist you in debugging.

若要运行此代码示例,请将其粘贴到包含继承的类型的实例的项目Control,如ButtonComboBoxTo run the example code, paste it into a project that contains an instance of a type that inherits from Control, such as a Button or ComboBox. 然后该实例命名Control1,并确保事件处理程序相关联GotFocus事件。Then name the instance Control1 and ensure that the event handler is associated with the GotFocus event.

private void Control1_GotFocus(Object sender, EventArgs e) {

   MessageBox.Show("You are in the Control.GotFocus event.");

}
Private Sub Control1_GotFocus(sender as Object, e as EventArgs) _ 
     Handles Control1.GotFocus

Console.WriteLine("You are in the Control.GotFocus event.")

End Sub

注解

将焦点更改通过使用键盘 (TAB、 SHIFT + TAB,等),通过调用SelectSelectNextControl方法,或通过设置ContainerControl.ActiveControl到当前窗体的属性,将按以下顺序发生焦点事件:When you change the focus by using the keyboard (TAB, SHIFT+TAB, and so on), by calling the Select or SelectNextControl methods, or by setting the ContainerControl.ActiveControl property to the current form, focus events occur in the following order:

  1. Enter

  2. GotFocus

  3. Leave

  4. Validating

  5. Validated

  6. LostFocus

当更改焦点,使用鼠标或通过调用Focus方法时,按以下顺序执行的焦点事件:When you change the focus by using the mouse or by calling the Focus method, focus events occur in the following order:

  1. Enter

  2. GotFocus

  3. LostFocus

  4. Leave

  5. Validating

  6. Validated

如果CausesValidation属性设置为false,则ValidatingValidated所抑制的事件。If the CausesValidation property is set to false, the Validating and Validated events are suppressed.

请注意GotFocusLostFocus事件是绑定到的 WM_KILLFOCUS 和 WM_SETFOCUS Windows 消息的低级别的焦点事件。Note The GotFocus and LostFocus events are low-level focus events that are tied to the WM_KILLFOCUS and WM_SETFOCUS Windows messages. 通常情况下,GotFocusLostFocus更新时仅使用事件UICues或编写自定义控件时。Typically, the GotFocus and LostFocus events are only used when updating UICues or when writing custom controls. 相反EnterLeave事件应使用的所有控件除了Form类,使用ActivatedDeactivate事件。Instead the Enter and Leave events should be used for all controls except the Form class, which uses the Activated and Deactivate events. 有关详细信息GotFocusLostFocus事件,请参阅WM_SETFOCUSWM_KILLFOCUS主题。For more information about the GotFocus and LostFocus events, see the WM_SETFOCUS and WM_KILLFOCUS topics.

注意

不尝试将焦点设置在EnterGotFocusLeaveLostFocusValidating,或Validated事件处理程序。Do not attempt to set focus from within the Enter, GotFocus, Leave, LostFocus, Validating, or Validated event handlers. 执行此操作可能会导致你的应用程序或操作系统停止响应。Doing so can cause your application or the operating system to stop responding. 有关详细信息,请参阅WM_KILLFOCUS主题。For more information, see the WM_KILLFOCUS topic.

有关处理事件的详细信息,请参阅处理和引发事件For more information about handling events, see Handling and Raising Events.

适用于

另请参阅