using System.IO;
string[] filePaths = Directory.GetFiles(@"c:\MyDir\");
// returns:
// "c:\MyDir\my-car.BMP"
// "c:\MyDir\my-house.jpg"
string[] filePaths = Directory.GetFiles(@"c:\MyDir\", "*.bmp");
// returns:
// "c:\MyDir\my-car.BMP"
string[] filePaths = Directory.GetFiles(@"c:\MyDir\", "*.bmp",
SearchOption.AllDirectories);
// returns:
// "c:\MyDir\my-car.BMP"
// "c:\MyDir\Friends\james.BMP"