Disable hot keys using c# RSS

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  nithra08

  Member

  1 Points

  75 Posts

  Disable hot keys using c#

  Mar 28, 2008 01:52 PM|LINK

  hi,

  i'm doing my application in asp.net with c#.

  i want to disable the hotkeys such as CTRL, ALT, ESC, ALT+F4,........

  i tried this code..but i get some number like 1400,1409 as the error message.

  i dont know how to solve this error... 

  using System;

  using System.Data;

  using System.Configuration;

  using System.Web;

  using System.Web.Security;

  using System.Web.UI;

  using System.Web.UI.WebControls;

  using System.Web.UI.WebControls.WebParts;

  using System.Web.UI.HtmlControls;

  using System.Collections;

  using System.ComponentModel;

  using System.Drawing;

  using System.Text;

  using System.Windows.Forms;

  using System.Runtime.InteropServices;

  using System.Diagnostics;

  /// <summary>

  /// Summary description for ki

  /// </summary>

  public partial class ki:Form

  {

  #region dll

  [DllImport("user32.dll")]

  private static extern int RegisterHotKey(IntPtr hwnd, int id, int fsModifiers, int vk);

  [DllImport("user32.dll")]

  private static extern int ShowWindow(int hwnd, int cmd);

  [DllImport("user32.dll")]

  private static extern int FindWindow(string cls, string wndwText);

   

  [DllImport("user32.dll")]

  private static extern int UnregisterHotKey(IntPtr hwnd, int id);

  #endregion

  #region con

  private const int USE_ALT = 1;

  private const int USE_CTRL = 2;

  short mHotKeyId = 0;

  #endregion

  public ki()

  {

  //

  // TODO: Add constructor logic here

  //

  //InitializeComponent();

   

  RegisterGlobalHotKey(Keys.F4, USE_ALT); <--------- i got the error message while executing this line

  RegisterGlobalHotKey(Keys.W, USE_CTRL);

  // Disable ALT+Tab - tab through open applications

  RegisterGlobalHotKey(Keys.Tab, USE_ALT);

  // hide the task bar - not a big deal, they can

  // still CTRL+ESC to get the start menu; for that

  // matter, CTRL+ALT+DEL also works; if you need to

  // disable that you will have to violate SAS and

  // monkey with the security policies on the machine

  //ShowWindow(FindWindow("Shell_TrayWnd", null), 0);

  }

  private void RegisterGlobalHotKey(Keys hotkey, int modifiers)

  {

  try

  {

  // increment the hot key value - we are just identifying

  // them with a sequential number since we have multiples

  mHotKeyId++;

  if(mHotKeyId > 0)

  {

  // register the hot key combination

  if (RegisterHotKey(this.Handle, mHotKeyId, modifiers, Convert.ToInt16(hotkey)) == 0)

  {

  // tell the user which combination failed to register

  // this is useful to you, not an end user; the user

  // should never see this application run

  MessageBox.Show("Error: " + mHotKeyId.ToString() + " - " +Marshal.GetLastWin32Error().ToString(),"HotKey Registration");

  }

  }

  }

  catch

  {

  // clean up if hotkey registration failed -

  // nothing works if it fails

  UnregisterGlobalHotKey();

  }

  }

  public void UnregisterGlobalHotKey()

  {

  // loop through each hotkey id and

  // disable it

  for (int i = 0; i < mHotKeyId; i++)

  {

  UnregisterHotKey(this.Handle, i);

  }

  }

  protected override void WndProc(ref Message m)

  {

  base.WndProc(ref m);

  // if the message matches,

  // disregard it

  const int WM_HOTKEY = 0x312;if (m.Msg == WM_HOTKEY)

  {

  // Ignore the request or each

  // disabled hotkey combination

  }

  }

  private void Form1_FormClosed(object sender, FormClosedEventArgs e)

  {

  UnregisterGlobalHotKey();

  // show the taskbar - does not matter really

  ShowWindow(FindWindow("Shell_TrayWnd", null), 1);

  }

  }

   

   

• • Reply
  

  Mikesdotnett...

  All-Star

  154927 Points

  19867 Posts

  Moderator

  MVP

  Re: Disable hot keys using c#

  Mar 28, 2008 02:10 PM|LINK

  Is this a Windows client app?  If so, you are better off posting here: http://windowsclient.net/.  It uses the same login as forums.asp.net, by the way.

   

  Regards, Mike
  Beginning ASP.NET Web Pages with WebMatrix | My Site | Twitter
  • Marked as answer by Hua-Jun Li - MSFT on Apr 03, 2008 04:04 AM