Question

VB向一个外部程序发送一条信息(回车键)

首先在窗体上添加一个command1 和 一个text1

Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long

Private Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long

Private Const WM_KEYDOWN = &H100

Private Const WM_KEYUP = &H101

Private Const VK_TAB = &H9

Private Sub Command1_Click()
Dim a As Long
a = FindWindow(vbNullString, Text1.Text)
SendMessage a, WM_KEYDOWN, VK_TAB, 0
SendMessage a, WM_KEYUP, VK_TAB, 0

End Sub

说明： 测试时，应先将接受按键消息的程序运行（可后台运行），然后在text1中输入程序窗体名（可程序名）点击command1即可发送tab消息

这个是发送TAB的，但现在我想发送回车键。请问如何是好呢？谢谢了。

Answer 1

实际上不必用费劲的常数，模拟按键都是PostMessage
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long

Private Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)

Private Declare Function PostMessage Lib "user32" Alias "PostMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Long) As Long

Private Const WM_KEYDOWN = &H100

Private Const WM_KEYUP = &H101

Private Sub Command1_Click()
Dim a As Long
a = FindWindow(vbNullString, Text1.Text)
PostMessage a, WM_KEYDOWN, vbKeyReturn, 0
End Sub

keybd_event也可以用这种方法

Answer 2

TAB键与回车键都是按键.
既然能够发送TAB(VK_TAB)键.为何转个弯了想呢? 不会是复制的吧