-Edit- I feel like an idiot. I had a feeling something like the answer below would work but didnt see any google results similar to the answers below. So when i saw this com
Assuming that you just want to launch files which already have some associated applications (eg: *.txt is associated with notepad), Use System.Diagnostics.Process.
e.g. :
using System.Diagnostics;
Process p = new Process();
ProcessStartInfo pi = new ProcessStartInfo();
pi.UseShellExecute = true;
pi.FileName = @"MY_FILE_WITH_FULL_PATH.jpg";
p.StartInfo = pi;
try
{
p.Start();
}
catch (Exception Ex)
{
//MessageBox.Show(Ex.Message);
}
Note: In my PC, the pic opens in Windows Picture & Fax Viewer since that is the default application for *.jpg files.