微分在keydown事件

问题描述：

输入键之间如果使用该keydown处理压在VB.net可以检测回车键：微分在keydown事件

Private Sub kd(sender As Object, e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown 
    IF e.key=key.Enter Then 
     <do your code> 
    Endif 
End Sub

然而，有一个方法告诉这两个输入键在键盘被按下？既然你有两个键盘（一个接一个地撇号（中间）和一个在数字键盘），我想有中间的输入按钮具有数字键盘不同的响应回车键输入键。

一个例子：在Photoshop中，用文本工具时，可以按中间进入添加文本的另一条线，或按小键盘进入确认你输入的内容。

答

从http://support.microsoft.com/kb/188550/en-us

代码在VB.net

Option Strict Off 
Option Explicit On 
Friend Class Form1 
    Inherits System.Windows.Forms.Form 
    Private Declare Function PeekMessage Lib "user32" Alias "PeekMessageA" (ByRef lpMsg As MSG, ByVal hwnd As Integer, ByVal wMsgFilterMin As Integer, ByVal wMsgFilterMax As Integer, ByVal wRemoveMsg As Integer) As Integer 

    Private Structure POINTAPI 
     Dim x As Integer 
     Dim y As Integer 
    End Structure 

    Private Structure MSG 
     Dim hwnd As Integer 
     Dim message As Integer 
     Dim wParam As Integer 
     Dim lParam As Integer 
     Dim time As Integer 
     Dim pt As POINTAPI 
    End Structure 

    Const PM_NOREMOVE As Integer = &H0 
    Const WM_KEYDOWN As Integer = &H100 
    Const WM_KEYUP As Integer = &H101 
    Const VK_RETURN As Integer = &HD 

    Private Sub Form1_KeyDown(ByVal eventSender As System.Object, ByVal eventArgs As System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyDown 
     Dim KeyCode As Short = eventArgs.KeyCode 
     Dim Shift As Short = eventArgs.KeyData \ &H10000 
     Dim MyMsg As MSG 
     Dim RetVal As Integer 

     ' pass: 
     ' MSG structure to receive message information 
     ' my window handle 
     ' low and high filter of 0, 0 to trap all messages 
     ' PM_NOREMOVE to leave the keystroke in the message queue 
     ' use PM_REMOVE (1) to remove it 
     RetVal = PeekMessage(MyMsg, Me.Handle.ToInt32, 0, 0, PM_NOREMOVE) 

     ' now, per Q77550, you should look for a MSG.wParam of VK_RETURN 
     ' if this was the keystroke, then test bit 24 of the lparam - if ON, 
     ' then keypad was used, otherwise, keyboard was used 
     If RetVal <> 0 Then 
      If MyMsg.wParam = VK_RETURN Then 
       If MyMsg.lParam And &H1000000 Then 
        MsgBox("Enter from Keypad pressed") 
       Else 
        MsgBox("Enter from Keyboard pressed") 
       End If 
      End If 
     Else 
      MsgBox("No message waiting, or possible problems calling PeekMessage") 
     End If 
    End Sub 
End Class

采取

微分在keydown事件

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