FileComparer.cs

/// <summary>
/// Sort files
/// <code> string folder = "c:\\windows\\";
/// string[] files = Directory.GetFiles(folder);
/// IComparer comp = new FileComparer(FileComparer.CompareBy.FileSize);
/// Array.Sort(files, comp);
/// foreach(string file in files)
/// {
///		Console.WriteLine(file);
/// } </code>
/// </summary>
public class FileComparer : IComparer
{
	public enum CompareBy
	{
		Name /* a-z */,
		LastWriteTime /* oldest to newest */,
		CreationTime  /* oldest to newest */,
		LastAccessTime /* oldest to newest */,
		FileSize /* smallest first */
	}
	// default comparison
	int _CompareBy = (int)CompareBy.Name;

	public FileComparer()
	{
	}

	public FileComparer(CompareBy compareBy)
	{
		_CompareBy = (int)compareBy;
	}

	int IComparer.Compare(object x, object y)
	{
		int output = 0;
		FileInfo file1 = new FileInfo(x.ToString());
		FileInfo file2 = new FileInfo(y.ToString());
		switch (_CompareBy)
		{
			case (int)CompareBy.LastWriteTime:
				output = DateTime.Compare(file1.LastWriteTime, file2.LastWriteTime);
				break;
			case (int)CompareBy.CreationTime:
				output = DateTime.Compare(file1.CreationTime, file2.CreationTime);
				break;
			case (int)CompareBy.LastAccessTime:
				output = DateTime.Compare(file1.LastAccessTime, file2.LastAccessTime);
				break;
			case (int)CompareBy.FileSize:
				output = Convert.ToInt32(file1.Length - file2.Length);
				break;
			case (int)CompareBy.Name:
			default:
				output = (new CaseInsensitiveComparer()).Compare(file1.Name, file2.Name);
				break;
		}
		return output;
	}
}