winform sendkey

Question

I'm an app and to spread. We select a button from the application. Secondly, we enter small parts, I cannot connect it to a key. ie "e" is requested to switch, and this e key "o" is reviewed.

Answer 1

@Zaug , If you want to run the keydown events even if the form is hidden, you could try to use Global keyboard monitoring(Hook) to do it.

Here is a code example you could refer to.

using System;  
using System.Runtime.InteropServices;  
using System.Windows.Forms;  
  
  class KeyboardHook  
    {  
        public event KeyEventHandler KeyDownEvent;  
        public event KeyPressEventHandler KeyPressEvent;  
        public event KeyEventHandler KeyUpEvent;  
  
        public delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam);  
        static int hKeyboardHook = 0;   
                                       
                                       
        public const int WH_KEYBOARD_LL = 13;     
        HookProc KeyboardHookProcedure;   
  
        [StructLayout(LayoutKind.Sequential)]  
        public class KeyboardHookStruct  
        {  
            public int vkCode;    
            public int scanCode;   
            public int flags;    
            public int time;   
            public int dwExtraInfo;   
        }  
   
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]  
        public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);  
  
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]  
        public static extern bool UnhookWindowsHookEx(int idHook);  
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]  
        public static extern int CallNextHookEx(int idHook, int nCode, Int32 wParam, IntPtr lParam);  
  
  
        [DllImport("kernel32.dll")]  
        static extern int GetCurrentThreadId();  
  
        [DllImport("kernel32.dll")]  
        public static extern IntPtr GetModuleHandle(string name);  
  
        public void Start()  
        {  
  
            if (hKeyboardHook == 0)  
            {  
                KeyboardHookProcedure = new HookProc(KeyboardHookProc);  
                hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, GetModuleHandle(System.Diagnostics.Process.GetCurrentProcess().MainModule.ModuleName), 0);  
                
                if (hKeyboardHook == 0)  
                {  
                    Stop();  
                    throw new Exception("Failed to install keyboard hook");  
                }  
            }  
        }  
        public void Stop()  
        {  
            bool retKeyboard = true;  
  
            if (hKeyboardHook != 0)  
            {  
                retKeyboard = UnhookWindowsHookEx(hKeyboardHook);  
                hKeyboardHook = 0;  
            }  
  
            if (!(retKeyboard)) throw new Exception("Failed to uninstall keyboard hook！");  
        }  
        [DllImport("user32")]  
        public static extern int ToAscii(int uVirtKey,   
                                         int uScanCode,   
                                         byte[] lpbKeyState,   
                                         byte[] lpwTransKey,   
                                         int fuState);   
  
  
        [DllImport("user32")]  
        public static extern int GetKeyboardState(byte[] pbKeyState);  
  
        [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]  
        private static extern short GetKeyState(int vKey);  
  
        private const int WM_KEYDOWN = 0x100;//KEYDOWN  
        private const int WM_KEYUP = 0x101;//KEYUP  
        private const int WM_SYSKEYDOWN = 0x104;//SYSKEYDOWN  
        private const int WM_SYSKEYUP = 0x105;//SYSKEYUP  
  
        private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)  
        {  
  
            if ((nCode >= 0) && (KeyDownEvent != null || KeyUpEvent != null || KeyPressEvent != null))  
            {  
                KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));  
                // raise KeyDown  
                if (KeyDownEvent != null && (wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN))  
                {  
                    Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;  
                    KeyEventArgs e = new KeyEventArgs(keyData);  
                    KeyDownEvent(this, e);  
                }  
  
  
                if (KeyPressEvent != null && wParam == WM_KEYDOWN)  
                {  
                    byte[] keyState = new byte[256];  
                    GetKeyboardState(keyState);  
  
                    byte[] inBuffer = new byte[2];  
                    if (ToAscii(MyKeyboardHookStruct.vkCode, MyKeyboardHookStruct.scanCode, keyState, inBuffer, MyKeyboardHookStruct.flags) == 1)  
                    {  
                        KeyPressEventArgs e = new KeyPressEventArgs((char)inBuffer[0]);  
                        KeyPressEvent(this, e);  
                    }  
                }  
  
  
                if (KeyUpEvent != null && (wParam == WM_KEYUP || wParam == WM_SYSKEYUP))  
                {  
                    Keys keyData = (Keys)MyKeyboardHookStruct.vkCode;  
                    KeyEventArgs e = new KeyEventArgs(keyData);  
                    KeyUpEvent(this, e);  
                }  
  
            }  
            return CallNextHookEx(hKeyboardHook, nCode, wParam, lParam);  
        }  
        ~KeyboardHook()  
        {  
            Stop();  
        }  
    }  

You could use it in the Form_Load event.

private void Form1_Load(object sender, EventArgs e)  
        {  
            var k_hook = new KeyboardHook();  
            k_hook.KeyDownEvent += new KeyEventHandler(hook_KeyDown);  
            k_hook.Start();  
        }  
        private void hook_KeyDown(object sender, KeyEventArgs e)  
        {  
  
            if (e.KeyValue >= (int)Keys.A &&e.KeyValue<=(int)Keys.Z )  
            {  
                System.Windows.Forms.MessageBox.Show(e.KeyCode.ToString());  
            }  
        }  

Result:

---

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Answer 2

when want my code file , this my code file

`using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Diagnostics;

namespace WinFormsApp1
{
public partial class Form1 : Form
{
private void comboBox2_SelectedIndexChanged(object sender, EventArgs e)
{
deger = comboBox2.SelectedItem.ToString();
}

    public Form1() : base()
    {            
        InitializeComponent();
        this.KeyPreview = true;
        //combobox1
        {
            comboBox1.Items.Add("A");
            comboBox1.Items.Add("B");
            comboBox1.Items.Add("C");
            comboBox1.Items.Add("D");
            comboBox1.Items.Add("E");
            comboBox1.Items.Add("F");
            comboBox1.Items.Add("G");
            comboBox1.Items.Add("H");
            comboBox1.Items.Add("İ");
            comboBox1.Items.Add("J");
            comboBox1.Items.Add("K");
            comboBox1.Items.Add("L");
            comboBox1.Items.Add("M");
            comboBox1.Items.Add("N");
            comboBox1.Items.Add("O");
            comboBox1.Items.Add("P");
            comboBox1.Items.Add("R");
            comboBox1.Items.Add("S");
            comboBox1.Items.Add("T");
            comboBox1.Items.Add("U");
            comboBox1.Items.Add("V");
            comboBox1.Items.Add("W");
            comboBox1.Items.Add("X");
            comboBox1.Items.Add("Y");
            comboBox1.Items.Add("Z");
        }
        //combobox2
        {
            comboBox2.Items.Add("A");
            comboBox2.Items.Add("B");
            comboBox2.Items.Add("C");
            comboBox2.Items.Add("D");
            comboBox2.Items.Add("E");
            comboBox2.Items.Add("F");
            comboBox2.Items.Add("G");
            comboBox2.Items.Add("H");
            comboBox2.Items.Add("İ");
            comboBox2.Items.Add("J");
            comboBox2.Items.Add("K");
            comboBox2.Items.Add("L");
            comboBox2.Items.Add("M");
            comboBox2.Items.Add("N");
            comboBox2.Items.Add("O");
            comboBox2.Items.Add("P");
            comboBox2.Items.Add("R");
            comboBox2.Items.Add("S");
            comboBox2.Items.Add("T");
            comboBox2.Items.Add("U");
            comboBox2.Items.Add("V");
            comboBox2.Items.Add("W");
            comboBox2.Items.Add("X");
            comboBox2.Items.Add("Y");
            comboBox2.Items.Add("Z");
        }
    }
    private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
    {
        secilenharf = comboBox1.SelectedItem.ToString();
        if (secilenharf == "A")
        {
            basilacakharf = "a";
        }
        if (secilenharf == "B")
        {
            basilacakharf = "b";
        }
        if (secilenharf == "C")
        {
            basilacakharf = "c";
        }
        if (secilenharf == "D")
        {
            basilacakharf = "d";
        }
        if (secilenharf == "E")
        {
            basilacakharf = "e";
        }
        if (secilenharf == "F")
        {
            basilacakharf = "f";
        }
        if (secilenharf == "G")
        {
            basilacakharf = "g";
        }
        if (secilenharf == "H")
        {
            basilacakharf = "h";
        }
        if (secilenharf == "İ")
        {
            basilacakharf = "i";
        }
        if (secilenharf == "J")
        {
            basilacakharf = "j";
        }
        if (secilenharf == "K")
        {
            basilacakharf = "k";
        }
        if (secilenharf == "L")
        {
            basilacakharf = "l";
        }
        if (secilenharf == "M")
        {
            basilacakharf = "m";
        }
        if (secilenharf == "N")
        {
            basilacakharf = "n";
        }
        if (secilenharf == "O")
        {
            basilacakharf = "o";
        }
        if (secilenharf == "P")
        {
            basilacakharf = "p";
        }
        if (secilenharf == "Q")
        {
            basilacakharf = "q";
        }
        if (secilenharf == "R")
        {
            basilacakharf = "r";
        }
        if (secilenharf == "S")
        {
            basilacakharf = "s";
        }
        if (secilenharf == "T")
        {
            basilacakharf = "t";
        }
        if (secilenharf == "U")
        {
            basilacakharf = "u";
        }
        if (secilenharf == "V")
        {
            basilacakharf = "v";
        }
        if (secilenharf == "W")
        {
            basilacakharf = "w";
        }
        if (secilenharf == "X")
        {
            basilacakharf = "x";
        }
        if (secilenharf == "Y")
        {
            basilacakharf = "y";
        }
        if (secilenharf == "Z")
        {
            basilacakharf = "z";
        }
    }
    private static void ShowWindow(IntPtr p, int v)
    {
    }


    //DEĞİŞKENLER
    bool oyunacildi = false;
    string oyunadı;
    string chardeger;
    string basilacakharf;
    string deger;
    string secilenharf = "NULL";

    //DEĞİŞKENLER BİTİŞ


    private void button1_Click(object sender, EventArgs e)
    {            
        OpenFileDialog gamename = new OpenFileDialog();
        gamename.Filter = "exe Dosyaları|*.exe";
        gamename.Title = "Oyun Seçin";
        if (gamename.ShowDialog() == DialogResult.OK)
        {

            button2.Visible = true;
            oyunadı = gamename.FileName;
            label1.Text += gamename.SafeFileName;
        }           
    }


    //oyunu açma---------------------------------------------
    private void button2_Click(object sender,EventArgs e)
    {
        oyunacildi = true;            
        if (basilacakharf == "a")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();           
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            if (chardeger == "A")
            {
                SendKeys.SendWait("a");
            }
            if (chardeger == "B")
            {
                SendKeys.SendWait("a");
            }
            if (chardeger == "C")
            {
                SendKeys.SendWait("a");
            }
            if (chardeger == "D")
            {
                SendKeys.SendWait("a");
            }

        }
        if (basilacakharf == "b")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("b");
        }
        if (basilacakharf == "c")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("c");
        }
        if (basilacakharf == "d")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("d");
        }
        if (basilacakharf == "e")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("e");
        }
        if (basilacakharf == "f")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("f");
        }
        if (basilacakharf == "h")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("h");
        }
        if (basilacakharf == "i")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("i");
        }
        if (basilacakharf == "j")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("j");
        }
        if (basilacakharf == "k")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("k");
        }
        if (basilacakharf == "l")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("l");
        }
        if (basilacakharf == "m")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("m");
        }
        if (basilacakharf == "n")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("n");
        }
        if (basilacakharf == "o")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("o");
        }
        if (basilacakharf == "p")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("p");
        }
        if (basilacakharf == "q")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("q");
        }
        if (basilacakharf == "r")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("r");
        }
        if (basilacakharf == "s")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("s");
        }
        if (basilacakharf == "t")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("t");
        }
        if (basilacakharf == "u")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("u");
        }
        if (basilacakharf == "v")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("v");
        }
        if (basilacakharf == "w")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("w");
        }
        if (basilacakharf == "x")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("x");
        }
        if (basilacakharf == "y")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("y");
        }
        if (basilacakharf == "z")
        {
            Process notepad = new Process();
            notepad.StartInfo.FileName = oyunadı;
            notepad.Start();
            notepad.WaitForInputIdle();
            IntPtr p = notepad.MainWindowHandle;
            ShowWindow(p, 1);
            SendKeys.SendWait("z");
        }
    }
    //oyunu açma bitiş---------------------------------------}

    private void Form1_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.KeyCode == Keys.A)
        {
            if(oyunacildi==true)
            {
                SendKeys.SendWait("O");
                chardeger = "A";
            }                
        }
        if (e.KeyCode == Keys.B)
        {
            chardeger = "B";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.C)
        {
            chardeger = "C";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.D)
        {
            chardeger = "D";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.E)
        {
            chardeger = "E";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.F)
        {
            chardeger = "F";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.G)
        {
            chardeger = "G";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.H)
        {
            chardeger = "H";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.I)
        {
            chardeger = "I";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.J)
        {
            chardeger = "J";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.K)
        {
            chardeger = "K";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.L)
        {
            chardeger = "L";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.M)
        {
            chardeger = "M";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.N)
        {
            chardeger = "N";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.O)
        {
            chardeger = "O";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.P)
        {
            chardeger = "P";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.Q)
        {
            chardeger = "Q";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.R)
        {
            chardeger = "R";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.S)
        {
            chardeger = "S";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.T)
        {
            chardeger = "T";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.U)
        {
            chardeger = "U";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.V)
        {
            chardeger = "V";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.W)
        {
            chardeger = "W";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.X)
        {
            chardeger = "X";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.Y)
        {
            chardeger = "Y";
            MessageBox.Show(chardeger);
        }
        if (e.KeyCode == Keys.Z)
        {
            chardeger = "Z";
            MessageBox.Show(chardeger);
        }                 
    }
}

}

Answer 3

Not sure exactly where the problem is so will not attempt to answer, instead suggest some refactoring so it's easier to maintain and for others to assist you.

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        readonly Dictionary<string, string> _dictionary = new Dictionary<string, string>();
        private string basilacakharf;
        public Form1()
        {
            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)
        {
            var alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray();


            foreach (var c in alphabet)
            {
                _dictionary.Add(c.ToString(), c.ToString().ToLower());
            }

            var source = alphabet.ToList();
            comboBox1.DataSource = source;
            comboBox2.DataSource = new List<char>(source);

            comboBox1.SelectedIndexChanged += ComboBox1OnSelectedIndexChanged;
        }


        private void ComboBox1OnSelectedIndexChanged(object sender, EventArgs e)
        {
            // same needed for second comboBox
            basilacakharf = _dictionary[comboBox1.Text];
            Text = $"comboBox1 {basilacakharf}";
        }
    }
}