public static string[] GetMXRecords(string domain)
{
IntPtr ptr1 = IntPtr.Zero;
IntPtr ptr2 = IntPtr.Zero;
MXRecord recMx;
if (Environment.OSVersion.Platform != PlatformID.Win32NT)
{
throw new NotSupportedException();
}
ArrayList list1 = new ArrayList();
int num1 = MxLookupHandler.DnsQuery(ref domain, QueryTypes.DNS_TYPE_MX, QueryOptions.DNS_QUERY_BYPASS_CACHE, 0, ref ptr1, 0);
if (num1 != 0)
{
throw new Win32Exception(num1);
}
for (ptr2 = ptr1; !ptr2.Equals(IntPtr.Zero); ptr2 = recMx.pNext)
{
recMx = (MXRecord)Marshal.PtrToStructure(ptr2, typeof(MXRecord));
if (recMx.wType == 15)
{
string text1 = Marshal.PtrToStringAuto(recMx.pNameExchange);
list1.Add(text1);
}
}
MxLookupHandler.DnsRecordListFree(ptr2, 0);
return((string[])list1.ToArray(typeof(string)));
}
private static MechanismResponse GetAutoconfigByDomain(string domain, RequestType requestType)
{
MechanismResponse returnVal = new MechanismResponse();
if (!string.IsNullOrEmpty(domain))
{
List <Mechanism> mechanisms = GetMechanisms();
switch (requestType)
{
case RequestType.Standard:
returnVal = AttemptAll(mechanisms, domain);
break;
case RequestType.MxLookup:
bool found = false;
string[] mxRecords = MxLookupHandler.GetMXRecordsTrimDistinct(domain);
if (mxRecords != null && mxRecords.Length > 0)
{
foreach (string mx in mxRecords)
{
returnVal = AttemptAll(mechanisms, mx);
found = returnVal != null && returnVal.IsSuccess;
if (found)
{
break;
}
}
if (!found) //Guess from the mx record
{
foreach (string mx in mxRecords)
{
returnVal = MxGuessHandler.GuessConfig(mx);
found = returnVal != null && returnVal.IsSuccess;
if (found)
{
break;
}
}
}
}
break;
case RequestType.Guess:
returnVal = MxGuessHandler.GuessConfig(domain);
break;
}
}
if (returnVal != null)
{
returnVal.RequestType = requestType;
}
return(returnVal);
}