How to open a file that contains some other extension like(.mxd) when button is click

[sohil]

How to open a file that contains some other extension like(.mxd) when button is click

[xMetalDetectorx]

How about trying FileStream class?

using System.IO;
 
FileStream fileStream = new FileStream(@"c:\file.txt", FileMode.Open);
try
{
  // read from file or write to file
}
finally
{
  fileStream.Close();
}
 

[Scotty Islegit]

private void OpenAsProcess(string path)
{
    if (!string.IsNullOrEmpty(path))
    {
        try
        {
            Process.Start(new ProcessStartInfo(path));
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
    }
}