C# | check if program/application is installed on remote computer

As an advance to my previous post about checking if a program or an application is installed on my comptuer, I bringing a code for doing this validation on a remote computer.

The code is the same as checking for installed app in local comptuer (as described here) except that checking remote machine registry.
The remote machine registry checking is preformed using the static method OpenRemoteBaseKey of the class RegistryKey.

The code:

public static bool IsAppInstalled(string p_machineName, string p_name)
{
   string keyName;
 
   // search in: CurrentUser
   keyName = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";
   if (ExistsInRemoteSubKey(p_machineName, RegistryHive.CurrentUser, keyName, "DisplayName", p_name) == true)
   {
      return true;
   }
 
   // search in: LocalMachine_32
   keyName = @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall";
   if (ExistsInRemoteSubKey(p_machineName, RegistryHive.LocalMachine, keyName, "DisplayName", p_name) == true)
   {
      return true;
   }
 
   // search in: LocalMachine_64
   keyName = @"SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall";
   if (ExistsInRemoteSubKey(p_machineName, RegistryHive.LocalMachine, keyName, "DisplayName", p_name) == true)
   {
      return true;
   }
 
   return false;
}
private static bool ExistsInRemoteSubKey(string p_machineName, RegistryHive p_hive, string p_subKeyName, string p_attributeName, string p_name)
{
   RegistryKey subkey;
   string displayName;
 
   using (RegistryKey regHive = RegistryKey.OpenRemoteBaseKey(p_hive, p_machineName))
   {
      using (RegistryKey regKey = regHive.OpenSubKey(p_subKeyName))
      {
         if (regKey != null)
         {
            foreach (string kn in regKey.GetSubKeyNames())
            {
               using (subkey = regKey.OpenSubKey(kn))
               {
                  displayName = subkey.GetValue(p_attributeName) as string;
                  if (p_name.Equals(displayName, StringComparison.OrdinalIgnoreCase) == true) // key found!
                  {
                     return true;
                  }
               }
            }
         }
      }
   }
   return false;
}
    

How to use this code:

string MACHINE_NAME = "MY-PC-NAME";
string APPLICATION_NAME = "APP-NAME";
try
{
bool isAppInstalled = IsAppInstalled(MACHINE_NAME, APPLICATION_NAME);
  string msg = string.Format("Application '{0}' is {1} on the remote-machine '{2}'!",
APPLICATION_NAME,
isAppInstalled ? "installed" : "NOT installed",
MACHINE_NAME);
MessageBox.Show(msg);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}

Enjoy...
MDB-Blog

Trim Image white-spaces (black&white) | C# Winforms

I searched for a simple code that preform "TRIMMING" to an image.
By "trimming" i mean, that if i have a LARGE image that contains information (painting/drawing...) only in small part of the image and all other is white-space (WHITE or BLACK pixels).

I needed to remove such whitespace and also to decrease image size.
Following three code examples:

Code #1 - Gets the NON-WHITE-SPACE bounds of an image

private Rectangle GetImageNonWhiteSpaceBounds(Bitmap p_img, bool p_isBlackWhitespace)
{
    Rectangle rect = new Rectangle();
    unsafe
    {
        BitmapData bdActual = null;
        try
        {
            int width = p_img.Width;
            int height = p_img.Height;

            bdActual = p_img.LockBits(new Rectangle(0, 0, width, height), System.Drawing.Imaging.ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
            Int32 i;
            Int32 pSize = 3;
            Byte whiteTrashold = (Byte)240;
            Byte blackTrashold = (Byte)10;
            Byte* sourceRow;

            Int32 minX = width;
            Int32 maxX = 0;
            Int32 minY = height;
            Int32 maxY = 0;
            bool isWhitepace;

            for (Int32 _y = 0; _y < height; ++_y)             {                 sourceRow = (Byte*)bdActual.Scan0 + (_y * bdActual.Stride);                 for (Int32 _x = 0; _x < width; ++_x)                 {                     i = _x * pSize;                     isWhitepace =                         (p_isBlackWhitespace && sourceRow[i] <= blackTrashold && sourceRow[i + 1] <= blackTrashold && sourceRow[i + 2] <= blackTrashold)                         ||                         (!p_isBlackWhitespace && sourceRow[i] >= whiteTrashold && sourceRow[i + 1] >= whiteTrashold && sourceRow[i + 2] >= whiteTrashold);

                    if (isWhitepace == false)
                    {
                        // NO whitespace!!!
                        minX = Math.Min(_x, minX);
                        maxX = Math.Max(_x, maxX);

                        minY = Math.Min(_y, minY);
                        maxY = Math.Max(_y, maxY);
                    }
                }
            }

            rect.X = minX;
            rect.Y = minY;
            rect.Width = maxX - minX;
            rect.Height = maxY - minY;
        }
        finally
        {
            if (bdActual != null)
            {
                p_img.UnlockBits(bdActual);
            }
        }
    }
    return rect;
}

Code #2 - Draw rectangle around the NON-WHITE-SPACE

private void DrawNonWhiteSpaceRectangle(Bitmap p_img, bool p_isBlackWhitespace, Color p_color)
{
    unsafe
    {
        BitmapData bdActual = null;
        try
        {
            int width = p_img.Width;
            int height = p_img.Height;

            bdActual = p_img.LockBits(new Rectangle(0, 0, width, height), System.Drawing.Imaging.ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
            Int32 i;
            Int32 pSize = 3;
            Byte whiteTrashold = (Byte)240;
            Byte blackTrashold = (Byte)10;
            Byte* sourceRow;

            Int32 minX = width;
            Int32 maxX = 0;
            Int32 minY = height;
            Int32 maxY = 0;
            bool isWhitepace;

            for (Int32 _y = 0; _y < height; ++_y)             {                 sourceRow = (Byte*)bdActual.Scan0 + (_y * bdActual.Stride);                 for (Int32 _x = 0; _x < width; ++_x)                 {                     i = _x * pSize;                     isWhitepace =                         (p_isBlackWhitespace && sourceRow[i] <= blackTrashold && sourceRow[i + 1] <= blackTrashold && sourceRow[i + 2] <= blackTrashold)                         ||                         (!p_isBlackWhitespace && sourceRow[i] >= whiteTrashold && sourceRow[i + 1] >= whiteTrashold && sourceRow[i + 2] >= whiteTrashold);

                    if (isWhitepace == false)
                    {
                        // NO whitespace!!!
                        minX = Math.Min(_x, minX);
                        maxX = Math.Max(_x, maxX);

                        minY = Math.Min(_y, minY);
                        maxY = Math.Max(_y, maxY);
                    }
                }
            }

            // draw rectagle:
            for (Int32 _y = minY; _y <= maxY; ++_y)             {                 sourceRow = (Byte*)bdActual.Scan0 + (_y * bdActual.Stride);                 i = minX * pSize;                 sourceRow[i] = (Byte)p_color.R;                 sourceRow[i + 1] = (Byte)p_color.G;                 sourceRow[i + 2] = (Byte)p_color.B;                 i = maxX * pSize;                 sourceRow[i] = (Byte)p_color.R;                 sourceRow[i + 1] = (Byte)p_color.G;                 sourceRow[i + 2] = (Byte)p_color.B;             }             Byte* sourceRowX1 = (Byte*)bdActual.Scan0 + (minY * bdActual.Stride);             Byte* sourceRowX2 = (Byte*)bdActual.Scan0 + (maxY * bdActual.Stride);             for (Int32 _x = minX; _x <= maxX; ++_x)             {                 i = _x * pSize;                 sourceRowX1[i] = (Byte)p_color.R;                 sourceRowX1[i + 1] = (Byte)p_color.G;                 sourceRowX1[i + 2] = (Byte)p_color.B;                 sourceRowX2[i] = (Byte)p_color.R;                 sourceRowX2[i + 1] = (Byte)p_color.G;                 sourceRowX2[i + 2] = (Byte)p_color.B;             }         }         finally         {             if (bdActual != null)             {                 p_img.UnlockBits(bdActual);             }         }     } }

Code #3 - Trim Image whitespaces

private Bitmap CropImageWhitespaces(Bitmap p_img, bool p_isBlackWhitespace)
{
    Rectangle rect = new Rectangle();
    unsafe
    {
        BitmapData bdActual = null;
        try
        {
            int width = p_img.Width;
            int height = p_img.Height;

            bdActual = p_img.LockBits(new Rectangle(0, 0, width, height), System.Drawing.Imaging.ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb);
            Int32 i;
            Int32 pSize = 3;
            Byte whiteTrashold = (Byte)240;
            Byte blackTrashold = (Byte)10;
            Byte* sourceRow;

            Int32 minX = width;
            Int32 maxX = 0;
            Int32 minY = height;
            Int32 maxY = 0;
            bool isWhitepace;

            for (Int32 _y = 0; _y < height; ++_y)             {                 sourceRow = (Byte*)bdActual.Scan0 + (_y * bdActual.Stride);                 for (Int32 _x = 0; _x < width; ++_x)                 {                     i = _x * pSize;                     isWhitepace =                         (p_isBlackWhitespace && sourceRow[i] <= blackTrashold && sourceRow[i + 1] <= blackTrashold && sourceRow[i + 2] <= blackTrashold)                         ||                         (!p_isBlackWhitespace && sourceRow[i] >= whiteTrashold && sourceRow[i + 1] >= whiteTrashold && sourceRow[i + 2] >= whiteTrashold);

                    if (isWhitepace == false)
                    {
                        // NO whitespace!!!
                        minX = Math.Min(_x, minX);
                        maxX = Math.Max(_x, maxX);

                        minY = Math.Min(_y, minY);
                        maxY = Math.Max(_y, maxY);
                    }
                }
            }

            rect.X = minX;
            rect.Y = minY;
            rect.Width = maxX - minX;
            rect.Height = maxY - minY;
        }
        finally
        {
            if (bdActual != null)
            {
                p_img.UnlockBits(bdActual);
            }
        }
    }

    return p_img.Clone(rect, p_img.PixelFormat);
}

I hope it will be helpful for you.
this code if fast and easy to use.

Javascript | Restrict number of open windows

Javascript Restrict number of open windows

here is a javascript code which allows:

• Check if window is open
• List open windows
• Manage 5 open windows (Any amount)
• Open restricted num. of windows.

function openWindowMAX5(p_url)
{
var win_I;
for(var i=0; i<5; i++)
{
win_I = window.open('', 'win_' + i);
if (win_I.document.location.href == 'about:blank')
{
window.status = 'win_'+i;
win_I = window.open(p_url, 'win_' + i);
break;
}
}
event.returnValue = false;
return false;
}

Used html code:
Open on new window

Tested on:

Working: IE7, CHROME 1.0.154

Not Working: Mozilla Firefox 3.0