SGIP接收DELIVER上行的问题(100分)

XDeliver=Record
UserNumber :array[0..20] of char;
SPNumber :array[0..27] of char;
TP_pid :byte;
TP_udhi :byte;
MessageCoding :byte;
MessageLength :longword;
MessageContent :array[0..254] of char;
Reserver :array[0..7] of char;
end;
var
ReDeliver:XDeliver;

if ReHead.CommandId=SGIP_DELIVER then
begin
FillChar(s_Pack,SizeOf(s_Pack),0);
FillChar(ReDeliver,SizeOf(ReDeliver),0);
//Socket.ReceiveBuf(Rechar,SizeOf(Rechar));
//memo2.Lines.Add('接收上行短信');
//memo2.Lines.add(Rechar);
Socket.ReceiveBuf(ReDeliver,SizeOf(ReDeliver));
memo2.Lines.Add('接收上行短信');
memo2.Lines.Add(inttostr(ReDeliver.MessageCoding)); //为什么得到的是50，而不是8(联通说应该是代表ucs2编码的8);
memo2.Lines.Add(inttostr(ReDeliver.TP_pid));
memo2.Lines.Add(inttostr(ReDeliver.TP_udhi));
memo2.Lines.Add(ReDeliver.UserNumber);
memo2.Lines.Add(inttostr(ReDeliver.MessageLength));
memo2.Lines.Add(ReDeliver.MessageContent));//不能得到正常的字符串，如何才能解码
memo2.Lines.Add(ReDeliver.SPNumber);
memo2.Lines.Add(ReDeliver.Reserver);//不能得到linkid值，为什么？
谢谢，请指教

请各位赐教 ，谢谢