使用Olevariant类型进行接收,并要转化成variant类型进行处理;
 var
  vtmp:variant
  ovtmp:olevariant; ovtmp:=mscomm.input;
 vtmp:=vararraycreate([0,3],varbyte);
 vtmp:=ovtmp;
 strinput:='';
 For i:=0 to 3 do
     begin
          btmp:=vtmp[i];
          str:=str+chr(btmp);
     end;