C# Signature:

[DllImport("iphlpapi.dll", SetLastError=true)]
static extern uint GetIpAddrTable([Out] IntPtr ipTable, [In,Out] IntPtr tableSize, bool sort);

VB Signature:

Declare Ansi Function
GetIpAddrTable Lib "iphlpapi.dll" (ByRef ipTable As IntPtr, ByRef tableSize As IntPtr, ByVal ordered As Boolean) As UInt32

Managed C++ Signature

[DllImport(S"IPHLPAPI.DLL", EntryPoint=S"GetIpAddrTable", SetLastError=true, CharSet=CharSet::Unicode, ExactSpelling=true)]
static UInt32 GetIpAddressTable( [Out] IntPtr ipTable, [In,Out] IntPtr tableSize, bool sort);

User-Defined Types:

None.

Alternative Managed API:

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Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

IntPtr pBuf = IntPtr.Zero;

int nBufSize = 0;

// get the required buffer size

GetIpAddrTable( IntPtr.Zero, ref nBufSize, false );

// allocate the buffer

pBuf = Marshal.AllocHGlobal( nBufSize );

int r = GetIpAddrTable( pBuf, ref nBufSize, false );

if ( r != 0 )

    throw new System.ComponentModel.Win32Exception( r );

int entrySize = Marshal.SizeOf(typeof(MIB_IPADDRROW));

int nEntries = Marshal.ReadInt32(pBuf);

int tableStartAddr = (int)pBuf + sizeof(int);

for (int i = 0; i < nEntries; i++)

{

    IntPtr pEntry = (IntPtr)(tableStartAddr + i * entrySize);
    MIB_IPADDRROW addrStruct = (MIB_IPADDRROW)Marshal.PtrToStructure(pEntry, typeof(MIB_IPADDRROW));
    string ipAddrStr = IPToString( IPAddress.NetworkToHostOrder(addrStruct._address) );
    string ipMaskStr = IPToString( IPAddress.NetworkToHostOrder(addrStruct._mask) );

}

if ( pBuf != IntPtr.Zero )

    Marshal.FreeHGlobal( pBuf );

// helper function IPToString

static string IPToString(int ipaddr)

{

    return String.Format( "{0}.{1}.{2}.{3}",
    (ipaddr >> 24) & 0xFF, (ipaddr >> 16) & 0xFF,
    (ipaddr >> 8) & 0xFF, ipaddr & 0xFF);

}