如何在键盘上检测[上，下，左，右]键。 [英] How to detect keys [up, down, left, right] on keyboard.

问题描述

如何检测键盘上的键[上，下，左，右]。

How to detect keys [up, down, left, right] on keyboard.

推荐答案

如果您使用的是Windows窗体，请在构造函数中添加：

If you are using Windows Forms, add this in the constructor:

Me.KeyPreview = True

然后创建此方法：

And then create this method:

Private Sub Form1_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown
	Select Case e.KeyCode
		Case Keys.Up
			' up arrow
			Exit Select
		Case Keys.Down
			' down arrow
			Exit Select
		Case Keys.Left
			' left arrow
			Exit Select
		Case Keys.Right
			' right arrow
			Exit Select
	End Select
End Sub

设置 KeyPreview 到 True 确保 Form1_KeyDown 将永远如果按下某个键，即使焦点位于另一个控件上，也可以调用，例如 TextBox 。



如果您使用的是WPF：

Setting KeyPreview to True makes sure that the Form1_KeyDown will always be called if a key is pressed, even if the focus is on another control, such as a TextBox.

If you are using WPF:

Private Sub MainWindow_PreviewKeyDown(sender As Object, e As KeyEventArgs) Handles Me.PreviewKeyDown
	Select Case e.Key
		Case Key.Up
			' up arrow
			Exit Select
		Case Key.Down
			' down arrow
			Exit Select
		Case Key.Left
			' left arrow
			Exit Select
		Case Key.Right
			' right arrow
			Exit Select
	End Select
End Sub

在WPF中， PreviewKeyDown 事件与Windows窗体中的 KeyPreview 属性具有相同的目的。如果您不想这样，只需使用 KeyDown 。



如果您使用的是控制台应用程序：

In WPF, the PreviewKeyDown event has the same purpose as the KeyPreview property in Windows Forms. If you don't want that, just use KeyDown.

If you are using a Console Application:

Dim c As ConsoleKeyInfo = Console.ReadKey()
Select Case c.Key
	Case ConsoleKey.UpArrow
		' up arrow
		Exit Select
	Case ConsoleKey.DownArrow
		' down arrow
		Exit Select
	Case ConsoleKey.LeftArrow
		' left arrow
		Exit Select
	Case ConsoleKey.RightArrow
		' right arrow
		Exit Select
End Select

请注意，这仅在您调用 Console.ReadKey（）时才有效。

有一个名为 Control.KeyDown [ ^ ]和 K eys [ ^ ] .NET中的枚举。



-KR

There's a event called Control.KeyDown[^] and Keys[^] enumeration in .NET.

-KR

这篇关于如何在键盘上检测[上，下，左，右]键。的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！