unit testunit;
inte***ce
uses
windows, messages, sysutils, variants, classes, graphics, controls, forms,
dialogs, stdctrls;
const
testmsgguid: tguid = '';
type
//原始介面中新增需要暴露給其它模組的介面定義，公用部分
itestmsg = inte***ce
['']
procedure showtestmsg;
end;
//---------------------------------服務模組
//基類物件，只需要開放showtestmsg方法給外部，所以做為按口的實現基類
tbasetestmsg = class(tinte***cedobject, itestmsg)
public
//.... 模組已存在的老**....
//新開放的介面**方法
procedure showtestmsg; virtual; //申明成虛擬方法，以便繼承類可以過載
end;
//---------------------------------介面委託物件定義
ttestmsgclass = class(tinte***cedobject, itestmsg)
private
ftestmsg: itestmsg;
public
property service: itestmsg read ftestmsg implements itestmsg;
constructor create(aclass: tclass);
constructor createex(aclass: tclass); //另一種用法, 不採用tbasetestmsg做為基類建立委託例項
destructor destroy; override;
end;
//----------------------------------外部引用的業務模組
//完成具體業務的委託例項
tetestmsg = class(tinte***cedobject, itestmsg)
public
procedure showtestmsg;
end;
//完成具體業務的委託例項
tctestmsg = class(tinte***cedobject, itestmsg)
public
procedure showtestmsg;
end;
tform1 = class(tform)
button1: tbutton;
button2: tbutton;
procedure button1click(sender: tobject);
procedure button2click(sender: tobject);
private
public
procedure dotest(aclass: tclass; acreateex: boolean = false); //測試方法
end;
varform1: tform1;
implementation
procedure tbasetestmsg.showtestmsg;
begin
end;
constructor ttestmsgclass.create(aclass: tclass);
varvobj: tbasetestmsg;
begin
vobj := tbasetestmsg(aclass.newinstance);
ftestmsg := vobj.create;
end;
constructor ttestmsgclass.createex(aclass: tclass);
begin
//該方法不採用tbasetestmsg做為基類建立委託例項，更通用更靈活
(aclass.newinstance.create).getinte***ce(testmsgguid, ftestmsg);
end;
destructor ttestmsgclass.destroy;
begin
ftestmsg := nil;
inherited;
end;
procedure tetestmsg.showtestmsg;
begin
showmessage('tetestmsg msg:' + 'ok');
end;
procedure tctestmsg.showtestmsg;
begin
showmessage('tctestmsg 訊息:' + '好的');
end;
//--------------------以下為測試**--------------------------------
procedure tform1.dotest(aclass: tclass; acreateex: boolean);
varvclass: ttestmsgclass;
vtest: itestmsg;
begin
if acreateex then
vclass := ttestmsgclass.createex(aclass)
else
vclass := ttestmsgclass.create(aclass);
tryvtest := vclass;
vtest.showtestmsg;
finally
vtest := nil;
freeandnil(vclass);
end;
end;
procedure tform1.button1click(sender: tobject);
begin
dotest(tetestmsg);
dotest(tctestmsg);
end;
procedure tform1.button2click(sender: tobject);
begin
dotest(tetestmsg, true);
dotest(tctestmsg, true);
end;
end.
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