C#

using System;
using System.Reflection; // For Missing.Value and BindingFlags
using System.Runtime.InteropServices; // For COMException
using Excel;

class AutoExcel {
	public static int Main() {
	
		Console.WriteLine ("Creating new Excel.Application");
		Application app = new Application();
		if (app == null) {
			Console.WriteLine("ERROR: EXCEL couldn't be started!");
			return 0;
		}
		
		Console.WriteLine ("Making application visible");		
		app.Visible = true;
		
		Console.WriteLine ("Getting the workbooks collection");
		Workbooks workbooks = app.Workbooks;

		Console.WriteLine ("Adding a new workbook");
		
		// The following line is the temporary workaround for the LCID problem
		_Workbook workbook = workbooks.Add(XlWBATemplate.xlWBATWorksheet);

...

System.Diagnostics.Process.Start("filename.xls");

private ArrayList tempFiles;

private string GetTempFilename(string extension)
{
   string tempFilename = Path.GetTempFileName();
   File.Move(tempFilename, tempFilename += ("." + extension));
   this.tempFiles.Add(tempFilename);

   return tempFilename;
}

// Make sure this gets attached to the right event.
private void MainForm_Closed(object sender, EventArgs e)
{
   foreach(string tempFile in this.tempFiles)
   {
      File.Delete(tempFile);
   }
}

// In any method, call this.GetTempFileName("tab").  It will return a 
// temporary .tab file, which will be cleaned up on the program's close.

public delegate void MyEvent(int SomeEventArgs);
public event MyEvent SomeEvent;

// then to call the event.
if (SomeEvent != null)
   SomeEvent(m_theEventArgs);

Email: theeclypse@hotmail.com   URL: http://www.onyeyiri.co.uk
"All programmers are playwrights and all computers are lousy actors."

Email: theeclypse@hotmail.com   URL: http://www.onyeyiri.co.uk
"All programmers are playwrights and all computers are lousy actors."

<configuration>
  <appSettings>
    <add key="settinga" value="valuea">
  </appSettings>
</configuration>

System.IO.File.Move("C:\\this.txt", "C:\\that.txt");

Bitmap bmp = new Bitmap(myImage);
bmp.MakeTransparent(Color.Green);

Email: theeclypse@hotmail.com   URL: http://www.onyeyiri.co.uk
"All programmers are playwrights and all computers are lousy actors."

<br />
CommandBarButton btn;<br />
Command          cmd;<br />
<br />
cmd=applicationObject.Commands.AddNamedCommand<br />
  (addInInstance, "MyCmd","Text","Tooltip",<br />
  false,1,  // Here i use bitmap from dll file "[TARGETDIR]\1033\Bitmaps.dll" with ID 1<br />
  ref contextGUIDS,<br />
  (int)vsCommandStatus.vsCommandStatusSupported+<br />
  (int)vsCommandStatus.vsCommandStatusEnabled);<br />
<br />
btn=MyCmd.AddControl(cmdBar,1) as CommandBarButton;<br />
        <br />