I have an application on Windows CE 5.0 and Windows Mobile 5.0 where I am currently fetching the IP address using the following code:
IPHostEntry dnsEntry = Dns.GetHostEntry(_host);
foreach (IPAddress ia in dnsEntry.AddressList)
{
if (ia.AddressFamily == AddressFamily.InterNetwork)
{
_address = ia;
break;
}
}
where "_host" is the hostname that is fetched from an XML config file. My question now is how do I see the remaining lease time for the IP address "_address"?
I'm leaving the previous answer as it may be useful for somebody else, but I think it's possible on Windows CE 5.0, using IP Helper API.
First, take a look at Managing Network Adapters (Windows CE 5.0).
You'll use the GetAdaptersInfo function.
It returns an IP_ADAPTER_INFO structure, that has an LeaseExpires
property.
Don't know if you ever used Windows API on C# before. It's a little ugly but you get used to it, and as long as it works, it's fine! =D
PInvoke.NET has a good example on how to use it. Don't know if it's related to the desktop or CE version, but I think you can manage to make it work.
It would be something like:
[DllImport("iphlpapi.dll", CharSet=CharSet.Ansi)]
public static extern int GetAdaptersInfo(IntPtr pAdapterInfo, ref Int64 pBufOutLen);
const int MAX_ADAPTER_DESCRIPTION_LENGTH = 128;
const int ERROR_BUFFER_OVERFLOW = 111;
const int MAX_ADAPTER_NAME_LENGTH = 256;
const int MAX_ADAPTER_ADDRESS_LENGTH = 8;
const int MIB_IF_TYPE_OTHER = 1;
const int MIB_IF_TYPE_ETHERNET = 6;
const int MIB_IF_TYPE_TOKENRING = 9;
const int MIB_IF_TYPE_FDDI = 15;
const int MIB_IF_TYPE_PPP = 23;
const int MIB_IF_TYPE_LOOPBACK = 24;
const int MIB_IF_TYPE_SLIP = 28;
public static void GetAdapters()
{
long structSize = Marshal.SizeOf( typeof( IP_ADAPTER_INFO ) );
IntPtr pArray = Marshal.AllocHGlobal( new IntPtr(structSize) );
int ret = GetAdaptersInfo( pArray, ref structSize );
if (ret == ERROR_BUFFER_OVERFLOW ) // ERROR_BUFFER_OVERFLOW == 111
{
// Buffer was too small, reallocate the correct size for the buffer.
pArray = Marshal.ReAllocHGlobal( pArray, new IntPtr (structSize) );
ret = GetAdaptersInfo( pArray, ref structSize );
} // if
if ( ret == 0 )
{
// Call Succeeded
IntPtr pEntry = pArray;
do
{
// Retrieve the adapter info from the memory address
IP_ADAPTER_INFO entry = (IP_ADAPTER_INFO)Marshal.PtrToStructure( pEntry, typeof( IP_ADAPTER_INFO ));
// ***Do something with the data HERE!***
Console.WriteLine("\n");
Console.WriteLine( "Index: {0}", entry.Index.ToString() );
// Adapter Type
string tmpString = string.Empty;
switch( entry.Type )
{
case MIB_IF_TYPE_ETHERNET : tmpString = "Ethernet"; break;
case MIB_IF_TYPE_TOKENRING : tmpString = "Token Ring"; break;
case MIB_IF_TYPE_FDDI : tmpString = "FDDI"; break;
case MIB_IF_TYPE_PPP : tmpString = "PPP"; break;
case MIB_IF_TYPE_LOOPBACK : tmpString = "Loopback"; break;
case MIB_IF_TYPE_SLIP : tmpString = "Slip"; break;
default : tmpString = "Other/Unknown"; break;
} // switch
Console.WriteLine( "Adapter Type: {0}", tmpString );
Console.WriteLine( "Name: {0}", entry.AdapterName );
Console.WriteLine( "Desc: {0}\n", entry.AdapterDescription );
Console.WriteLine( "DHCP Enabled: {0}", ( entry.DhcpEnabled == 1 ) ? "Yes" : "No" );
if (entry.DhcpEnabled == 1)
{
Console.WriteLine( "DHCP Server : {0}", entry.DhcpServer.IpAddress.Address );
// Lease Obtained (convert from "time_t" to C# DateTime)
DateTime pdatDate = new DateTime(1970, 1, 1).AddSeconds( entry.LeaseObtained ).ToLocalTime();
Console.WriteLine( "Lease Obtained: {0}", pdatDate.ToString() );
// Lease Expires (convert from "time_t" to C# DateTime)
pdatDate = new DateTime(1970, 1, 1).AddSeconds( entry.LeaseExpires ).ToLocalTime();
Console.WriteLine( "Lease Expires : {0}\n", pdatDate.ToString() );
} // if DhcpEnabled
Console.WriteLine( "IP Address : {0}", entry.IpAddressList.IpAddress.Address );
Console.WriteLine( "Subnet Mask : {0}", entry.IpAddressList.IpMask.Address );
Console.WriteLine( "Default Gateway: {0}", entry.GatewayList.IpAddress.Address );
// MAC Address (data is in a byte[])
tmpString = string.Empty;
for (int i = 0; i < entry.AddressLength - 1; i++)
{
tmpString += string.Format("{0:X2}-", entry.Address[i]);
}
Console.WriteLine( "MAC Address : {0}{1:X2}\n", tmpString, entry.Address[entry.AddressLength - 1] );
Console.WriteLine( "Has WINS: {0}", entry.HaveWins ? "Yes" : "No" );
if (entry.HaveWins)
{
Console.WriteLine( "Primary WINS Server : {0}", entry.PrimaryWinsServer.IpAddress.Address );
Console.WriteLine( "Secondary WINS Server: {0}", entry.SecondaryWinsServer.IpAddress.Address );
} // HaveWins
// Get next adapter (if any)
pEntry = entry.Next;
}
while( pEntry != IntPtr.Zero );
Marshal.FreeHGlobal(pArray);
} // if
else
{
Marshal.FreeHGlobal(pArray);
throw new InvalidOperationException( "GetAdaptersInfo failed: " + ret );
}
} // GetAdapters