[Csharp] Window Context Menu

Today, I read some topic on http://diendan.congdongcviet.com/
I found an enjoyable question on this topic: http://diendan.congdongcviet.com/showthread.php?t=85813
Create an custom menu in Window Context Menu, that I never thought. Get code of creator, I try to make menu.
After some minutes, I successfully create it. Then I have same question, how can get clicked file to my application. Try some ways and search Google. Yes, solution in here:
http://www.jfitz.com/tips/rclick_custom.html
Now, I will show you how to make a menu and do something with file.

For create new menu and remove it, I write a class:

   1:      public static class WindowContextMenu

   2:      {

   3:          public static void RemoveContextMenuItem(string extension, string menuName)

   4:          {

   5:              RegistryKey registryKey = Registry.ClassesRoot.OpenSubKey(extension);

   6:   

   7:              if (registryKey != null)

   8:              {

   9:                  string extstring = registryKey.GetValue("").ToString(); //root

  10:   

  11:                  registryKey.Close();

  12:   

  13:                  if (!string.IsNullOrEmpty(extstring))

  14:                  {

  15:                      registryKey = Registry.ClassesRoot.OpenSubKey(extstring, true);

  16:                      if (registryKey != null)

  17:                      {

  18:                          RegistryKey subky = registryKey.OpenSubKey("shell\\" + menuName);

  19:                          if ( subky != null )

  20:                          {

  21:                              subky.Close();

  22:                              registryKey.DeleteSubKeyTree("shell\\" + menuName);

  23:                              registryKey.Close();

  24:                          }

  25:                      }

  26:                  }

  27:              }

  28:          }

  29:   

  30:          public static void AddContextMenuItem(string extension, string menuName, string menuDescription, string menuCommand)

  31:          {

  32:              RegistryKey registryKey = Registry.ClassesRoot.OpenSubKey(extension);

  33:   

  34:              if (registryKey != null)

  35:              {

  36:                  string extstring = registryKey.GetValue("").ToString(); //root

  37:   

  38:                  registryKey.Close();

  39:   

  40:                  if (!string.IsNullOrEmpty(extstring))

  41:                  {

  42:                      registryKey = Registry.ClassesRoot.OpenSubKey(extstring, true);

  43:   

  44:                      if (registryKey != null)

  45:                      {

  46:                          string strkey = "shell\\" + menuName + "\\command";

  47:   

  48:                          RegistryKey subky = registryKey.CreateSubKey(strkey);

  49:   

  50:                          if (subky != null)

  51:                          {

  52:                              subky.SetValue("", menuCommand);

  53:                              subky.Close();

  54:                          }

  55:   

  56:                          subky = registryKey.OpenSubKey("shell\\" + menuName, true);

  57:                          if (subky != null)

  58:                          {

  59:                              subky.SetValue("", menuDescription);

  60:                              subky.Close();

  61:                          }

  62:                          registryKey.Close();

  63:                      }

  64:                  }

  65:              }

  66:          }

  67:      }

You can simply understand, it only write and delete key on Registry Editor. So, for use this class here is my sample:

   1:          private void btnRemove_Click(object sender, EventArgs e)

   2:          {

   3:              WindowContextMenu.RemoveContextMenuItem(".xls", "NewMenuOption");

   4:          }

   5:   

   6:          private void btnCreate_Click(object sender, EventArgs e)

   7:          {

   8:              WindowContextMenu.AddContextMenuItem(".xls", "NewMenuOption", "QuangHoang", Application.ExecutablePath + " \"%1\"");

   9:          }

This is code for two buttons Add and Remove.

So, now is the answer of question of topic I mention in top of post.

How your application open file? 
You can use args parameter. When user click on your menu, you can run you application and send file path to. Your application get the path and do what you want. Like this:

   1:          static void Main(string[] args)

   2:          {

   3:              Application.EnableVisualStyles();

   4:              Application.SetCompatibleTextRenderingDefault(false);

   5:   

   6:              if (args != null && args.Length > 0)

   7:              {

   8:                  Application.Run(new FormDemo(args[0]));

   9:              }

  10:              else Application.Run(new FormDemo());

  11:          }

Here, I am overload constructor of Main form.

How can get file's path user click on?
You can see on code I demo in above, you can see menuCommad parameter is Application.ExecutablePath + " \"%1\""
 - First part is path of you application, you can set what you want
 - Second part is "%1", it mean path of file you click on.

Source demo: http://www.mediafire.com/?qdg4ler3gt0guat
I think it so useful for some application.
Enjoy it :)