小编use*_*403的帖子

我有一个Packet抽象方法的类getID:

Type
  Packet = class
    ...
    function getID() : Integer;virtual;abstract;
    class procedure writePacket(par0 : Packet; par1 : TIdTCPConnection);
    ...
implementation 

class procedure Packet.writePacket(par0 : Packet; par1 : TIdTCPConnection);
// par1 is a TCP connection used to send data through the network; 
begin
  par1.writeInteger(par0.getID());
  //some code following 
end;

我有以下子类:

type
  PacketTest = class(Packet)
    ...
    function getID() : Integer;
    ...

function PacketTest.getID():Integer;
begin
  result := {some value individual for each subclass}
end;

现在我writePacket用包的子类调用超类的类过程,par0然后调用子类的函数getID …