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copied!<p>Here is the extra fast solution, that I finally implemented. Here I am using WinAPI and functions <em>FindFirstFile</em>, <em>FindNextFile</em>. It allows to avoid enumeration of all items in Folder and <strong>stops right after detecting the first object in the Folder</strong>. This approach is ~6(!!) times faster, than described above. 250 calls in 36ms!</p> <pre><code>private static readonly IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1); [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)] private struct WIN32_FIND_DATA { public uint dwFileAttributes; public System.Runtime.InteropServices.ComTypes.FILETIME ftCreationTime; public System.Runtime.InteropServices.ComTypes.FILETIME ftLastAccessTime; public System.Runtime.InteropServices.ComTypes.FILETIME ftLastWriteTime; public uint nFileSizeHigh; public uint nFileSizeLow; public uint dwReserved0; public uint dwReserved1; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)] public string cFileName; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 14)] public string cAlternateFileName; } [DllImport("kernel32.dll", CharSet=CharSet.Auto)] private static extern IntPtr FindFirstFile(string lpFileName, out WIN32_FIND_DATA lpFindFileData); [DllImport("kernel32.dll", CharSet=CharSet.Auto)] private static extern bool FindNextFile(IntPtr hFindFile, out WIN32_FIND_DATA lpFindFileData); [DllImport("kernel32.dll")] private static extern bool FindClose(IntPtr hFindFile); public static bool CheckDirectoryEmpty_Fast(string path) { if (string.IsNullOrEmpty(path)) { throw new ArgumentNullException(path); } if (Directory.Exists(path)) { if (path.EndsWith(Path.DirectorySeparatorChar.ToString())) path += "*"; else path += Path.DirectorySeparatorChar + "*"; WIN32_FIND_DATA findData; var findHandle = FindFirstFile(path, out findData); if (findHandle != INVALID_HANDLE_VALUE) { try { bool empty = true; do { if (findData.cFileName != "." && findData.cFileName != "..") empty = false; } while (empty && FindNextFile(findHandle, out findData)); return empty; } finally { FindClose(findHandle); } } throw new Exception("Failed to get directory first file", Marshal.GetExceptionForHR(Marshal.GetHRForLastWin32Error())); } throw new DirectoryNotFoundException(); } </code></pre> <p>I hope it will be useful for somebody in the future. </p>

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