TTCPClientEx = class(TIdTCPClient)
  private
    { Private declarations }
  protected
    { Protected declarations }
     public
    { Public declarations }
    constructor Create(AOwner: TComponent;IP:String;nPort:Integer); overload;
    destructor Destroy;override;
....
destructor TTCPClientEx.Destroy ;
begin
   inherited Destroy;
end;
constructor TTCPClientEx.Create(AOwner: TComponent);
begin
   inherited Create(AOwner);
//这里的代码不能执行??? 
   Host := IP;
   Port := nPort;
end;