Following the advice from this thread: distinguish between keyboard's Real and Virtual key presses
I'm trying to create a program, that will send keyboard's key-press events using SendInput() method.
However, the problem is that when I try to simulate a key press event - nothing happens whatsoever. So far that's my code:
[DllImport("user32.dll")]
static extern UInt32 SendInput(UInt32 nInputs, [MarshalAs(UnmanagedType.LPArray, SizeConst = 1)] INPUT[] pInputs, Int32 cbSize);
[StructLayout(LayoutKind.Sequential)]
struct KEYBDINPUT
{
public short wScan; public int dwFlags;
public int time; public IntPtr dwExtraInfo;
}
[StructLayout(LayoutKind.Explicit)]
struct INPUT
{
[FieldOffset(0)] public int type;
[FieldOffset(8)] public KEYBDINPUT ki; //x64 - 8, x32 - 4
}
const int KEYEVENTF_DOWN = 0; //key UP
const int KEYEVENTF_EXTENDEDKEY = 0x0001;
const int KEYEVENTF_KEYUP = 0x0002; //key UP
const int KEYEVENTF_UNICODE = 0x0004;
const int KEYEVENTF_SCANCODE = 0x0008; // scancode
public void Send_Key(short Keycode)
{
INPUT[] InputData = new INPUT[1];
InputData[0].type = 1;
InputData[0].ki.wScan = Keycode;
InputData[0].ki.dwFlags = KEYEVENTF_KEYUP | KEYEVENTF_SCANCODE;
InputData[0].ki.time = 0;
InputData[0].ki.dwExtraInfo = IntPtr.Zero;
SendInput(1, InputData, Marshal.SizeOf(typeof(INPUT)));
}
To decipher the scancodes I've downloaded the program that was suggested in this thread:
https://superuser.com/questions/293609/windows-7-tool-to-capture-keyboard-scan-codes
according to this program - "a" key's code for my keyboard is "65"
My program is supposed to trigger a key press event when textbox text is changed, so if we enter "q" - the text should change to "q" plus the result of send_key(), i.e. "qa":
private void textBox2_TextChanged(object sender, EventArgs e)
{
Send_Key(0x0065); // nothing happens (0x65 also fails)
}
what am I doing wrong? In the future I'll be changing this code so I can specify key-hold time (between DOWN and UP events). but for now, for testing purposes I'm simulating only keyUP event.
EDIT: Hans, according to your advice here is the edit - but it doesn't work, unfortunately.
public void Send_Key(short Keycode)
{
INPUT[] InputData = new INPUT[1];
InputData[0].type = 1;
InputData[0].ki.wScan = Keycode;
InputData[0].ki.dwFlags = KEYEVENTF_DOWN;
InputData[0].ki.time = 0;
InputData[0].ki.dwExtraInfo = IntPtr.Zero;
uint intReturn = SendInput(1, InputData, Marshal.SizeOf(typeof(INPUT)));
if (intReturn == 0) //!=1
{
throw new Exception("Could not send keyDOWN: " + Keycode);
}
INPUT[] InputData2 = new INPUT[1];
InputData2[0].type = 1;
InputData2[0].ki.wScan = Keycode;
InputData2[0].mi.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP | KEYEVENTF_SCANCODE;
InputData2[0].ki.time = 0;
InputData2[0].ki.dwExtraInfo = IntPtr.Zero;
uint intReturn2 = SendInput(1, InputData2, Marshal.SizeOf(typeof(INPUT)));
if (intReturn2 == 0) //!=1
{
throw new Exception("Could not send keyUP: " + Keycode);
}
}
no errors.. and no output.
