如何創建lParam的SendMessage WM_KEYDOWN

我試圖用SendMessage發送一個按鍵，並不真正瞭解lParam。我知道不同的位代表每個參數，並且他們需要按順序排列。如何創建lParam的SendMessage WM_KEYDOWN

我讀過this question & this，所以我知道這責令位需要在，我只是不知道該怎麼辦呢？

我將如何創建以下lParam的？

repeat cound = 0, 
scan code = {Don't know what this is?}, 
extended key = 1, 
reserved = 0, 
context code = 0, 
previous key state = 1, 
transition state = 0

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2012-04-23 Drahcir

作爲鏈接後國家，不要使用SendMessage函數發送鍵擊，使用SendInput代替。 http://blogs.msdn.com/b/oldnewthing/archive/2005/05/30/423202.aspx – 2012-04-23 11:56:40

@RussC：謝謝，但它需要與SendMessage完成，因爲我想將密鑰發送到其他窗口比活動的。真的，我只需要知道如何構建這個lParam。 – Drahcir 2012-04-23 12:13:41

我已在下面更新了我的答案。你能澄清你將發送WM_KEYDOWN消息給SendMessage嗎？ – 2012-04-23 12:32:38

我意識到AutoIT有我需要的功能，所以有看了看source文件sendKeys.cpp，發現該功能下面的C++代碼片段，這將是很容易轉化爲C＃：

scan = MapVirtualKey(vk, 0); 

// Build the generic lparam to be used for WM_KEYDOWN/WM_KEYUP/WM_CHAR 
lparam = 0x00000001 | (LPARAM)(scan << 16);   // Scan code, repeat=1 
if (bForceExtended == true || IsVKExtended(vk) == true) 
    lparam = lparam | 0x01000000;  // Extended code if required 

if ((m_nKeyMod & ALTMOD) && !(m_nKeyMod & CTRLMOD)) // Alt without Ctrl 
    PostMessage(m_hWnd, WM_SYSKEYDOWN, vk, lparam | 0x20000000); // Key down, AltDown=1 
else 
    PostMessage(m_hWnd, WM_KEYDOWN, vk, lparam); // Key down

掃描代碼可以根兒ated與MapVirtualKey

C＃翻譯：

public static void sendKey(IntPtr hwnd, VKeys keyCode, bool extended) 
{ 
    uint scanCode = MapVirtualKey((uint)keyCode, 0); 
    uint lParam; 

    //KEY DOWN 
    lParam = (0x00000001 | (scanCode << 16)); 
    if (extended) 
    { 
     lParam |= 0x01000000; 
    } 
    PostMessage(hwnd, (UInt32)WMessages.WM_KEYDOWN, (IntPtr)keyCode, (IntPtr)lParam); 

    //KEY UP 
    lParam |= 0xC0000000; // set previous key and transition states (bits 30 and 31) 
    PostMessage(hwnd, WMessages.WM_KEYUP, (uint)keyCode, lParam); 
} 

[DllImport("user32.dll", CharSet = CharSet.Auto)] 
private static extern uint MapVirtualKey(uint uCode, uint uMapType);

來源

2012-04-23 13:03:02 Drahcir