C# Signature:
[DllImport("netapi32.dll",EntryPoint="NetServerEnum")]
public static extern int NetServerEnum(
[MarshalAs(UnmanagedType.LPWStr)] string servername,
int level,
out IntPtr bufptr,
int prefmaxlen,
out int entriesread,
out int totalentries,
int servertype,
[MarshalAs(UnmanagedType.LPWStr)] string domain,
IntPtr resume_handle);
[DllImport("netapi32.dll",EntryPoint="NetApiBufferFree")]
public static extern int NetApiBufferFree(IntPtr buffer);
VB Signature:
Private Declare Unicode Function NetServerEnum Lib "netapi32" _
(ByVal Servername As IntPtr, _
ByVal Level As Integer, _
ByRef bufptr As IntPtr, _
ByVal PrefMaxLen As Integer, _
ByRef entriesread As Integer, _
ByRef TotalEntries As Integer, _
ByVal serverType As Integer, _
ByVal Domain As IntPtr, _
ByVal ResumeHandle As IntPtr) As Integer
Notes:
None.
Tips & Tricks:
Please add some!
Sample Code:
Sample Class #1
using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Security;
namespace Microsoft.Win32
{
internal static partial class NativeMethods
{
const int MAX_PREFERRED_LENGTH = -1;
[Flags]
public enum ServerTypes : uint
{
Workstation = 0x00000001,
Server = 0x00000002,
SqlServer = 0x00000004,
DomainCtrl= 0x00000008,
BackupDomainCtrl= 0x00000010,
TimeSource= 0x00000020,
AppleFilingProtocol = 0x00000040,
Novell= 0x00000080,
DomainMember = 0x00000100,
PrintQueueServer = 0x00000200,
DialinServer = 0x00000400,
XenixServer = 0x00000800,
UnixServer = 0x00000800,
NT = 0x00001000,
WindowsForWorkgroups = 0x00002000,
MicrosoftFileAndPrintServer= 0x00004000,
NTServer = 0x00008000,
BrowserService = 0x00010000,
BackupBrowserService= 0x00020000,
MasterBrowserService= 0x00040000,
DomainMaster = 0x00080000,
OSF1Server = 0x00100000,
VMSServer = 0x00200000,
Windows = 0x00400000,
DFS = 0x00800000,
NTCluster = 0x01000000,
TerminalServer= 0x02000000,
VirtualNTCluster = 0x04000000,
DCE = 0x10000000,
AlternateTransport = 0x20000000,
LocalListOnly = 0x40000000,
PrimaryDomain = 0x80000000,
All = 0xFFFFFFFF
};
public enum ServerPlatform
{
DOS = 300,
OS2 = 400,
NT = 500,
OSF = 600,
VMS = 700
}
[DllImport("Netapi32", CharSet = CharSet.Auto, SetLastError = true), SuppressUnmanagedCodeSecurityAttribute]
private static extern int NetServerEnum(
[MarshalAs(UnmanagedType.LPWStr)] string servernane, // must be null
int level,
out IntPtr bufptr,
int prefmaxlen,
out int entriesread,
out int totalentries,
ServerTypes servertype,
[MarshalAs(UnmanagedType.LPWStr)] string domain, // null for login domain
IntPtr resume_handle // Must be IntPtr.Zero
);
[DllImport("Netapi32", SetLastError = true), SuppressUnmanagedCodeSecurityAttribute]
private static extern int NetApiBufferFree(IntPtr pBuf);
[StructLayout(LayoutKind.Sequential)]
private struct SERVER_INFO_100
{
public ServerPlatform sv100_platform_id;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)]
public string sv100_name;
}
[StructLayout(LayoutKind.Sequential)]
public struct NetworkComputerInfo // SERVER_INFO_101
{
ServerPlatform sv101_platform_id;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)]
string sv101_name;
int sv101_version_major;
int sv101_version_minor;
ServerTypes sv101_type;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)]
string sv101_comment;
public ServerPlatform Platform { get { return sv101_platform_id; } }
public string Name { get { return sv101_name; } }
public string Comment { get { return sv101_comment; } }
public ServerTypes ServerTypes { get { return sv101_type; } }
public Version Version { get { return new Version(sv101_version_major, sv101_version_minor); } }
};
public static IEnumerable<string> GetNetworkComputerNames(ServerTypes serverTypes = ServerTypes.Workstation | ServerTypes.Server, string domain = null)
{
IntPtr bufptr = IntPtr.Zero;
try
{
int entriesRead, totalEntries;
IntPtr resumeHandle = IntPtr.Zero;
int ret = NetServerEnum(null, 100, out bufptr, MAX_PREFERRED_LENGTH, out entriesRead, out totalEntries, serverTypes, domain, resumeHandle);
if (ret == 0)
return Array.ConvertAll<SERVER_INFO_100, string>(InteropUtil.ToArray<SERVER_INFO_100>(bufptr, entriesRead), si => si.sv100_name);
throw new System.ComponentModel.Win32Exception(ret);
}
finally
{
NetApiBufferFree(bufptr);
}
}
public static IEnumerable<NetworkComputerInfo> GetNetworkComputerInfo(ServerTypes serverTypes = ServerTypes.Workstation | ServerTypes.Server, string domain = null)
{
IntPtr bufptr = IntPtr.Zero;
try
{
int entriesRead, totalEntries;
IntPtr resumeHandle = IntPtr.Zero;
int ret = NetServerEnum(null, 101, out bufptr, MAX_PREFERRED_LENGTH, out entriesRead, out totalEntries, serverTypes, domain, resumeHandle);
if (ret == 0)
return InteropUtil.ToArray<NetworkComputerInfo>(bufptr, entriesRead);
throw new System.ComponentModel.Win32Exception(ret);
}
finally
{
NetApiBufferFree(bufptr);
}
}
}
}
namespace System.Runtime.InteropServices
{
internal static class InteropUtil
{
public static T ToStructure<T>(IntPtr ptr)
{
return (T)Marshal.PtrToStructure(ptr, typeof(T));
}
/// <summary>
/// Converts an <see cref="IntPtr"/> that points to a C-style array into a CLI array.
/// </summary>
/// <typeparam name="T">Type of native structure used by the C-style array.</typeparam>
/// <param name="ptr">The <see cref="IntPtr"/> pointing to the native array.</param>
/// <param name="count">The number of items in the native array.</param>
/// <returns>An array of type <typeparamref name="T"/> containing the elements of the native array.</returns>
public static T[] ToArray<T>(IntPtr ptr, int count)
{
IntPtr tempPtr;
T[] ret = new T[count];
int stSize = Marshal.SizeOf(typeof(T));
for (int i = 0; i < count; i++)
{
tempPtr = new IntPtr(ptr.ToInt64() + (i * stSize));
ret[i] = ToStructure<T>(tempPtr);
}
return ret;
}
}
}
Sample Class #2
using System;
using System.Runtime.InteropServices;
using System.Collections ;
namespace Win32
{
/// <summary>
/// Summary description for Class1.
/// </summary>
///
public class NetApi32
{
// constants
public const uint ERROR_SUCCESS = 0;
public const uint ERROR_MORE_DATA = 234;
public enum SV_101_TYPES:uint
{
SV_TYPE_WORKSTATION= 0x00000001,
SV_TYPE_SERVER= 0x00000002,
SV_TYPE_SQLSERVER = 0x00000004,
SV_TYPE_DOMAIN_CTRL= 0x00000008,
SV_TYPE_DOMAIN_BAKCTRL= 0x00000010,
SV_TYPE_TIME_SOURCE= 0x00000020,
SV_TYPE_AFP= 0x00000040,
SV_TYPE_NOVELL= 0x00000080,
SV_TYPE_DOMAIN_MEMBER = 0x00000100,
SV_TYPE_PRINTQ_SERVER = 0x00000200,
SV_TYPE_DIALIN_SERVER = 0x00000400,
SV_TYPE_XENIX_SERVER = 0x00000800,
SV_TYPE_SERVER_UNIX = 0x00000800,
SV_TYPE_NT = 0x00001000,
SV_TYPE_WFW = 0x00002000,
SV_TYPE_SERVER_MFPN= 0x00004000,
SV_TYPE_SERVER_NT = 0x00008000,
SV_TYPE_POTENTIAL_BROWSER = 0x00010000,
SV_TYPE_BACKUP_BROWSER= 0x00020000,
SV_TYPE_MASTER_BROWSER= 0x00040000,
SV_TYPE_DOMAIN_MASTER = 0x00080000,
SV_TYPE_SERVER_OSF= 0x00100000,
SV_TYPE_SERVER_VMS= 0x00200000,
SV_TYPE_WINDOWS= 0x00400000,
SV_TYPE_DFS= 0x00800000,
SV_TYPE_CLUSTER_NT= 0x01000000,
SV_TYPE_TERMINALSERVER= 0x02000000,
SV_TYPE_CLUSTER_VS_NT = 0x04000000,
SV_TYPE_DCE= 0x10000000,
SV_TYPE_ALTERNATE_XPORT= 0x20000000,
SV_TYPE_LOCAL_LIST_ONLY= 0x40000000,
SV_TYPE_DOMAIN_ENUM= 0x80000000,
SV_TYPE_ALL= 0xFFFFFFFF
};
[StructLayout(LayoutKind.Sequential)]
public struct SERVER_INFO_101
{
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.U4)]
public UInt32 sv101_platform_id;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)]
public string sv101_name;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.U4)] public UInt32 sv101_version_major;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.U4)] public UInt32 sv101_version_minor;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.U4)] public UInt32 sv101_type;
[MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)] public string sv101_comment;
};
public enum PLATFORM_ID
{
PLATFORM_ID_DOS = 300,
PLATFORM_ID_OS2 = 400,
PLATFORM_ID_NT = 500,
PLATFORM_ID_OSF = 600,
PLATFORM_ID_VMS = 700
}
[DllImport("netapi32.dll",EntryPoint="NetServerEnum")]
public static extern int NetServerEnum( [MarshalAs(UnmanagedType.LPWStr)]string servername,
int level,
out IntPtr bufptr,
int prefmaxlen,
ref int entriesread,
ref int totalentries,
SV_101_TYPES servertype,
[MarshalAs(UnmanagedType.LPWStr)]string domain,
IntPtr resume_handle);
[DllImport("netapi32.dll",EntryPoint="NetApiBufferFree")]
public static extern int
NetApiBufferFree(IntPtr buffer);
[DllImport ("Netapi32", CharSet=CharSet.Unicode)]
private static extern int NetMessageBufferSend(
string servername,
string msgname,
string fromname,
string buf,
int buflen);
public static int NetMessageSend(string serverName,string messageName,string fromName,string strMsgBuffer, int iMsgBufferLen)
{
return NetMessageBufferSend(serverName,messageName,fromName,strMsgBuffer,iMsgBufferLen*2);
}
public static ArrayList GetServerList( NetApi32.SV_101_TYPES ServerType)
{
int entriesread=0,totalentries=0;
ArrayList alServers = new ArrayList();
do
{
// Buffer to store the available servers
// Filled by the NetServerEnum function
IntPtr buf = new IntPtr();
SERVER_INFO_101 server;
int ret = NetServerEnum(null,101,out buf,-1,
ref entriesread,ref totalentries,
ServerType,null,IntPtr.Zero);
// if the function returned any data, fill the tree view
if( ret == ERROR_SUCCESS ||
ret == ERROR_MORE_DATA ||
entriesread > 0)
{
IntPtr ptr = buf;
for(int i=0; i<entriesread; i++)
{
// cast pointer to a SERVER_INFO_101 structure
server = (SERVER_INFO_101)Marshal.PtrToStructure(ptr,typeof(SERVER_INFO_101));
//Cast the pointer to a ulong so this addition will work on 32-bit or 64-bit systems.
ptr = (IntPtr)((ulong)ptr + (ulong)Marshal.SizeOf(server));
// add the machine name and comment to the arrayList.
//You could return the entire structure here if desired
alServers.Add( server);
}
}
// free the buffer
NetApiBufferFree(buf);
}
while
(
entriesread < totalentries &&
entriesread != 0
);
return alServers;
}
}
}
Alternative Managed API:
Do you know one? Please contribute it!
The System.Data.Sql.SqlDataSourceEnumerator class is an alternative to this API, for enumerating SQL Servers on a network.
