Question

向Edit控件发送WM_SETTEXT消息时，不能改变该控件的内容。 这是为什么呢。

我想向一个游戏窗口的Edit子控件发送WM_SETTEXT消息来改变该控件的内容。但是改变不了， 也试过用 WM_CHAR,WM_KEYDOWN WM_KEYUP 也都不可以。这是为什么。 我另外试了一下 ，用MFC生成了一个程序A，其中有Edit控件，给A的Edit控件 发送消息时，可以改变内容，这是为什么呢。

Answer 1

'给你一个测试例
Option Explicit
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) 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 Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Const WM_SETTEXT = &HC
Private Sub Command1_Click()
    Dim s As String, myhwnd As Long
    s = "明白了吗？"
    myhwnd = FindWindow(vbNullString, "abc.txt - 记事本")
    myhwnd = FindWindowEx(myhwnd, 0&, "Edit", vbNullString) '控件名用spy++查看，这里是Edit，特定的软件控件名都是固定的
    If myhwnd = 0 Then
        MsgBox "新建或打开一个abc.txt文件在运行"
        Exit Sub
    End If
    SendMessage myhwnd, WM_SETTEXT, 0, ByVal s
End Sub

Answer 2

碰到SB了呗。

Answer 3

啥游戏有的游戏会把这些消息屏蔽了