I am trying to use the SendInput API but it doesn't seem to work from a Windows service.
Using the exact same code I can achieve the result I want from a Windows form, but not from a Windows service. I am assuming there is something I need to change, but I cant figure out what. I have checked and the problem has to be with the following code.
Here is my code with handles the api:
Using the exact same code I can achieve the result I want from a Windows form, but not from a Windows service. I am assuming there is something I need to change, but I cant figure out what. I have checked and the problem has to be with the following code.
Here is my code with handles the api:
Code:
using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
namespace WindowsUIInput
{
public class KeyboardInput
{
#region SendInput API
[DllImport("user32.dll", EntryPoint = "SendInput", SetLastError = true)]
static extern uint SendInput(uint nInputs, INPUT[] pInputs, int cbSize);
[DllImport("user32.dll", EntryPoint = "GetMessageExtraInfo", SetLastError = true)]
static extern IntPtr GetMessageExtraInfo();
public enum Key : ushort
{
SHIFT = 0x10,
CONTROL = 0x11,
MENU = 0x12,
ESCAPE = 0x1B,
BACK = 0x08,
TAB = 0x09,
RETURN = 0x0D,
PRIOR = 0x21,
NEXT = 0x22,
END = 0x23,
HOME = 0x24,
LEFT = 0x25,
UP = 0x26,
RIGHT = 0x27,
DOWN = 0x28,
SELECT = 0x29,
PRINT = 0x2A,
EXECUTE = 0x2B,
SNAPSHOT = 0x2C,
INSERT = 0x2D,
DELETE = 0x2E,
HELP = 0x2F,
NUMPAD0 = 0x60,
NUMPAD1 = 0x61,
NUMPAD2 = 0x62,
NUMPAD3 = 0x63,
NUMPAD4 = 0x64,
NUMPAD5 = 0x65,
NUMPAD6 = 0x66,
NUMPAD7 = 0x67,
NUMPAD8 = 0x68,
NUMPAD9 = 0x69,
MULTIPLY = 0x6A,
ADD = 0x6B,
SEPARATOR = 0x6C,
SUBTRACT = 0x6D,
DECIMAL = 0x6E,
DIVIDE = 0x6F,
F1 = 0x70,
F2 = 0x71,
F3 = 0x72,
F4 = 0x73,
F5 = 0x74,
F6 = 0x75,
F7 = 0x76,
F8 = 0x77,
F9 = 0x78,
F10 = 0x79,
F11 = 0x7A,
F12 = 0x7B,
OEM_1 = 0xBA, // ',:' for US
OEM_PLUS = 0xBB, // '+' any country
OEM_COMMA = 0xBC, // ',' any country
OEM_MINUS = 0xBD, // '-' any country
OEM_PERIOD = 0xBE, // '.' any country
OEM_2 = 0xBF, // '/?' for US
OEM_3 = 0xC0, // '`~' for US
MEDIA_NEXT_TRACK = 0xB0,
MEDIA_PREV_TRACK = 0xB1,
MEDIA_STOP = 0xB2,
MEDIA_PLAY_PAUSE = 0xB3,
LWIN = 0x5B,
RWIN = 0x5C,
A = 0x41,
B = 0x42,
C = 0x43,
D = 0x44,
E = 0x45,
F = 0x46,
G = 0x47,
H = 0x48,
I = 0x49,
J = 0x4A,
K = 0x4B,
L = 0x4C,
M = 0x4D,
N = 0x4E,
O = 0x5F,
P = 0x50,
Q = 0x51,
R = 0x52,
S = 0x53,
T = 0x54,
U = 0x55,
V = 0x56,
W = 0x57,
X = 0x58,
Y = 0x59,
Z = 0x5A,
}
private enum KeyEvent
{
KeyUp = 0x0002,
KeyDown = 0x0000,
ExtendedKey = 0x0001
}
private struct KEYBDINPUT
{
public ushort wVk;
public ushort wScan;
public uint dwFlags;
public long time;
public uint dwExtraInfo;
};
[StructLayout(LayoutKind.Explicit, Size = 28)]
private struct INPUT
{
[FieldOffset(0)]
public uint type;
[FieldOffset(4)]
public KEYBDINPUT ki;
};
#endregion
public static void Send(KeyboardInputStruct Kbi)
{
List<Key> KeysHoldDown = Kbi.KeysHeldDown;
List<Key> KeysPressed = Kbi.KeysPressed;
foreach (Key keyHeld in KeysHoldDown)
{
//Keydown the key.
INPUT keyInput = new INPUT();
keyInput.type = 1;
keyInput.ki.wScan = 0;
keyInput.ki.time = 0;
keyInput.ki.dwFlags = (int)KeyEvent.KeyDown;
keyInput.ki.dwExtraInfo = (uint)GetMessageExtraInfo();
keyInput.ki.wVk = (ushort)keyHeld;
INPUT[] keyInputs = { keyInput };
SendInput(1, keyInputs, Marshal.SizeOf(keyInput));
}
foreach (Key keyPress in KeysPressed)
{
//Key down the key.
INPUT keyInput = new INPUT();
keyInput.type = 1;
keyInput.ki.wScan = 0;
keyInput.ki.time = 0;
keyInput.ki.dwFlags = (int)KeyEvent.KeyDown;
keyInput.ki.dwExtraInfo = (uint)GetMessageExtraInfo();
keyInput.ki.wVk = (ushort)keyPress;
INPUT[] keyInputs = { keyInput };
SendInput(1, keyInputs, Marshal.SizeOf(keyInput));
//Key up the key.
keyInput.ki.dwFlags = (int)KeyEvent.KeyUp;
INPUT[] keyInputs2 = { keyInput };
SendInput(1, keyInputs2, Marshal.SizeOf(keyInput));
}
KeysHoldDown.Reverse();
foreach (Key keyHeld in KeysHoldDown)
{
INPUT keyInput = new INPUT();
keyInput.type = 1;
keyInput.ki.wScan = 0;
keyInput.ki.time = 0;
keyInput.ki.dwFlags = (int)KeyEvent.KeyUp;
keyInput.ki.dwExtraInfo = (uint)GetMessageExtraInfo();
keyInput.ki.wVk = (ushort)keyHeld;
INPUT[] keyInputs = { keyInput };
SendInput(1, keyInputs, Marshal.SizeOf(keyInput));
}
}
public struct KeyboardInputStruct
{
public List<Key> KeysPressed;
public List<Key> KeysHeldDown;
public KeyboardInputStruct(bool create)
{
KeysPressed = new List<Key>();
KeysHeldDown = new List<Key>();
}
}
}
}
Last edited: