问题
I am running a c# application that makes use of the sendinputs method in windows to mimic keystrokes. It works fine when I am remoted into the instance, but as soon as I log out it throws an exception. Can anyone offer any thoughts on why this is happening, and how to avoid it?
UPDATE:: here is some sample code that can reproduce the issue.
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace ConsoleApplication6
{
class Program
{
class SendKey
{
[StructLayout(LayoutKind.Sequential)]
private struct MOUSEINPUT
{
public int dx;
public int dy;
public int mouseData;
public int dwFlags;
public int time;
public int dwExtraInfo;
};
[StructLayout(LayoutKind.Sequential)]
private struct KEYBDINPUT
{
public short wVk;
public short wScan;
public int dwFlags;
public int time;
public int dwExtraInfo;
};
[StructLayout(LayoutKind.Sequential)]
private struct HARDWAREINPUT
{
public int uMsg;
public short wParamL;
public short wParamH;
};
[StructLayout(LayoutKind.Explicit)]
private struct INPUT
{
[FieldOffset(0)]
public int type;
[FieldOffset(4)]
public MOUSEINPUT no;
[FieldOffset(4)]
public KEYBDINPUT ki;
[FieldOffset(4)]
public HARDWAREINPUT hi;
};
[DllImport("user32.dll")]
private extern static void SendInput(int nInputs, ref INPUT pInputs, int cbsize);
[DllImport("user32.dll", EntryPoint = "MapVirtualKeyA")]
private extern static int MapVirtualKey(int wCode, int wMapType);
private const int INPUT_KEYBOARD = 1;
private const int KEYEVENTF_KEYDOWN = 0x0;
private const int KEYEVENTF_KEYUP = 0x2;
private const int KEYEVENTF_EXTENDEDKEY = 0x1;
private void Send(Keys key, bool isEXTEND)
{
INPUT inp = new INPUT();
inp.type = INPUT_KEYBOARD;
inp.ki.wVk = (short)key;
inp.ki.wScan = (short)MapVirtualKey(inp.ki.wVk, 0);
inp.ki.dwFlags = ((isEXTEND) ? (KEYEVENTF_EXTENDEDKEY) : 0x0) | KEYEVENTF_KEYDOWN;
inp.ki.time = 0;
inp.ki.dwExtraInfo = 0;
SendInput(1, ref inp, Marshal.SizeOf(inp));
System.Threading.Thread.Sleep(100);
inp.ki.dwFlags = ((isEXTEND) ? (KEYEVENTF_EXTENDEDKEY) : 0x0) | KEYEVENTF_KEYUP;
SendInput(1, ref inp, Marshal.SizeOf(inp));
}
static void Main()
{
while(true)
{
System.Threading.Thread.Sleep(2000);
SendKey s = new SendKey();
s.Send(Keys.Z, false);
s.Send(Keys.Left, true);
}
}
}
}
}
if you build this and just run it on a free windows server ec2 instance with notepad in focus it will print zzzzzz continuously while you are remoted into the instance, however, as soon as you remote out of the instance, it will stop printing until you log back in.
来源：https://stackoverflow.com/questions/36476576/windows-sendinput-keyboard-not-working-on-disconnect