C# Signature:
[DllImport("kernel32.dll")]
static extern bool GetFileTime(IntPtr hFile, IntPtr lpCreationTime,
IntPtr lpLastAccessTime, IntPtr lpLastWriteTime);
VB.Net Signature:
<DllImport( _
"kernel32.dll", _
CharSet:=CharSet.Auto, _
SetLastError:=True)> _
Friend Shared Function GetFileTime( _
ByVal hFile As IntPtr, _
<Out()> ByRef lpCreationTime As FILETIME, _
<Out()> ByRef lpLastAccessTime As FILETIME, _
<Out()> ByRef lpLastWriteTime As FILETIME) _
As Boolean
End Function
User-Defined Types:
None.
Notes:
None.
Tips & Tricks:
Please add some!
Sample Code:
private const uint GENERIC_READ = 0x80000000;
private const uint FILE_SHARE_READ = 0x1;
private const uint FILE_ATTRIBUTE_NORMAL = 0x80;
private const int INVALID_HANDLE_VALUE = -1;
private const uint OPEN_EXISTING = 3;
[StructLayout(LayoutKind.Sequential)]
private struct FILETIME
{
public uint dwLowDateTime;
public uint dwHighDateTime;
public DateTime ToDateTime()
{
return DateTime.FromFileTimeUtc((((long)dwHighDateTime) << 32) | ((uint)dwLowDateTime));
}
}
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CloseHandle(
IntPtr hObject
);
[DllImport("kernel32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)]
private static extern IntPtr CreateFile(
string lpFileName,
uint dwDesiredAccess,
uint dwShareMode,
IntPtr SecurityAttributes,
uint dwCreationDisposition,
uint dwFlagsAndAttributes,
IntPtr hTemplateFile
);
[DllImport("kernel32.dll", SetLastError = true)]
private static extern bool GetFileTime(
IntPtr hFile,
ref FILETIME lpCreationTime,
ref FILETIME lpLastAccessTime,
ref FILETIME lpLastWriteTime
);
private static void GetFileTimes(string FileName, out DateTime CreationTime, out DateTime LastAccessTime, out DateTime LastWriteTime)
{
CreationTime = DateTime.MinValue;
LastAccessTime = DateTime.MinValue;
LastWriteTime = DateTime.MinValue;
IntPtr ptr = IntPtr.Zero;
FILETIME ftCreationTime = new FILETIME();
FILETIME ftLastAccessTime = new FILETIME();
FILETIME ftLastWriteTime = new FILETIME();
try
{
ptr = CreateFile(@"c:\1.txt", GENERIC_READ, FILE_SHARE_READ, IntPtr.Zero, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, IntPtr.Zero);
if (ptr.ToInt32() == INVALID_HANDLE_VALUE)
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
if (GetFileTime(ptr, ref ftCreationTime, ref ftLastAccessTime, ref ftLastWriteTime) != true)
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
CreationTime = DateTime.FromFileTimeUtc((((long)ftCreationTime.dwHighDateTime) << 32) | ((uint)ftCreationTime.dwLowDateTime));
LastAccessTime = DateTime.FromFileTimeUtc((((long)ftLastAccessTime.dwHighDateTime) << 32) | ((uint)ftLastAccessTime.dwLowDateTime));
LastWriteTime = DateTime.FromFileTimeUtc((((long)ftLastWriteTime.dwHighDateTime) << 32) | ((uint)ftLastWriteTime.dwLowDateTime));
}
catch (Exception e)
{
throw (e);
}
finally
{
if (ptr !=IntPtr.Zero && ptr.ToInt32() != INVALID_HANDLE_VALUE) CloseHandle(ptr);
}
}
Alternative Managed API:
class System.IO.FileInfo,
members CreationTime and others.
