C# Signature:

[DllImport("netapi32.dll", SetLastError=true)]
static extern TODO NetFileEnum(TODO);

VB Signature:

Declare Function NetFileEnum Lib "netapi32.dll" ( _
    ByVal servername As String, _
    ByVal basepath As String, _
    ByVal username As String, _
    ByVal level As Integer, _
    ByRef bufptr As IntPtr, _
    ByVal prefmaxlen As Integer, _
    ByRef entriesread As Integer, _
    ByRef totalentries As Integer, _
    ByVal resume_handle As IntPtr) As Integer

User-Defined Types:

(one of 3 valid types)

    <StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Auto, Pack:=4)> _
    Structure FILE_INFO_3
    Dim fi3_id As Integer
    Dim fi3_permission As Integer
    Dim fi3_num_locks As Integer
    Dim fi3_pathname As String
    Dim fi3_username As String
    End Structure

Notes:

Definition from the API

    'NET_API_STATUS NetFileEnum(
    '  LPWSTR servername,
    '  LPWSTR basepath,
    '  LPWSTR username,
    '  DWORD level,
    '  LPBYTE* bufptr,
    '  DWORD prefmaxlen,
    '  LPDWORD entriesread,
    '  LPDWORD totalentries,
    '  PDWORD_PTR resume_handle
    ');

Tips & Tricks:

You must free the memory allocated to the bufptr with the NetApiBufferFree function

Sample Code:

    Const MAX_PREFERRED_LENGTH As Integer = -1
    Dim dwIndex, dwStatus, dwReadEntries, dwTotalEntries As Integer
    Dim pCurrent As FILE_INFO_3
    Dim iPtr, pBuffer As IntPtr

    dwStatus = NetFileEnum(TextBox1.Text, Nothing, Nothing, 3, pBuffer, MAX_PREFERRED_LENGTH, dwReadEntries, dwTotalEntries, Nothing)
    if dwStatus = 0 then
        For dwIndex = 0 To dwReadEntries - 1

        iPtr = New IntPtr(pBuffer.ToInt32 + (dwIndex * Len(pCurrent)))
        pCurrent = CType(Marshal.PtrToStructure(iPtr, GetType(FILE_INFO_3)), FILE_INFO_3)

        Debug.WriteLine("dwIndex=" & dwIndex)
        Debug.WriteLine("   id: " & pCurrent.fi3_id)
        Debug.WriteLine("   num_locks: " & pCurrent.fi3_num_locks)
        Debug.WriteLine("   pathname: " & pCurrent.fi3_pathname)
        Debug.WriteLine("   permission: " & pCurrent.fi3_permission)
        Debug.WriteLine("   username: " & pCurrent.fi3_username)
        Next
     end if

Alternative Managed API:

Do you know one? Please contribute it!