delphi 泛型 c++builder 泛型

delphi 泛型

System.Generics.Collections.pas

TList<T> 
http://docwiki.embarcadero.com/Libraries/Berlin/en/System.Generics.Collections.TList
http://docwiki.embarcadero.com/CodeExamples/Berlin/en/Generics_Collections_TList_(Delphi)
http://docwiki.embarcadero.com/CodeExamples/Berlin/en/Generics_Collections_TObjectList_(Delphi)
http://docwiki.embarcadero.com/Libraries/Berlin/en/System.Generics.Collections.TObjectList

listTime: TList<string>;
listVal: TList<Double>;

listVal: TList<integer>;

objlist:TObjectList<TEdit>;

alist:TList;//这个不是泛型

alist.add（是指针无类型）

List.LastIndexOf

list.add

List.AddRange([11,22,33]);

list.indexof

List.Reverse;

list.count;

list.item[i];

objlist.item[i];

list.Exchange

　　使用TObjectList<T>会将对象自动销毁，使用TList<T>不会将对象自动销毁。

TArray.Sort<string>(arr);

TArray.BinarySearch

http://docwiki.embarcadero.com/RADStudio/XE6/en/How_to_Handle_Delphi_Generics_in_C%2B%2B

这个泛型是为delphi编写的，c++builder不能直接使用，非要用的话按下面的例子，先建立个delphiunit，集成新类，然后再c++builder引用此单元头文件，就可以了。真麻烦。

c++builder还是用map、vector方便。

How to Handle Delphi Generics in C++

Go Up to Handling Delphi Features in C++Builder Index

This topic describes some programming issues that you might encounter when dealing with generics, a feature supported by Delphi.

Delphi generics are exposed to C++ as templates. However, it is important to realize that the instantiations occur on the Delphi side, not in C++. Therefore, you can only use these template for types that were explicitly instantiated in Delphi code. For example, let's declare a simple generic, TList<T>, in Delphi:

 
unit DelphiUnit;
 
interface
  uses System.Generics.Collections;
 
type
  MyTList<T> = class(TList<T>)
  public
    // Anchors constructor/destructor
    constructor Create;
    destructor Destroy; override;
 
    class procedure Cleanup(var L: MyTList<T>); static;
  end;
 
  // DoubleList: instantiates MyTList<double>
  DoubleList = class(MyTList<double>)
  end;
 
  // StringList: instantiates MyTList<string>
  StringList = class(MyTList<string>)
  end;
 
implementation
 
class procedure MyTList<T>.Cleanup(var L: MyTList<T>);
begin
  L.Free;
end;
 
constructor MyTList<T>.Create;
begin
  inherited;
end;
 
destructor MyTList<T>.Destroy;
begin
  inherited;
end;
 
end.

The interface above is exposed to C++ as the following:

 
// CodeGear C++Builder
// Copyright (c) 1995, 2012 by Embarcadero Technologies, Inc.
// All rights reserved
 
// (DO NOT EDIT: machine generated header) 'DelphiUnit.pas' rev: 24.00 (Windows)
 
#ifndef DelphiunitHPP
#define DelphiunitHPP
 
#pragma delphiheader begin
#pragma option push
#pragma option -w       // Display all warnings
#pragma option -w-inl   // Functions %s are not expanded inline
#pragma option -w-8111  // Accessing deprecated entity
#pragma option -Vx      // Zero-length empty class member
#pragma pack(push,8)
#include <System.hpp>	// Pascal unit
#include <SysInit.hpp>	// Pascal unit
#include <System.Generics.Collections.hpp>	// Pascal unit
#include <System.Generics.Defaults.hpp>	// Pascal unit
#include <System.Types.hpp>	// Pascal unit
 
//-- user supplied -----------------------------------------------------------
 
namespace Delphiunit
{
//-- type declarations -------------------------------------------------------
template<typename T> class DELPHICLASS MyTList__1;
// Template declaration generated by Delphi parameterized types is
// used only for accessing Delphi variables and fields.
// Don't instantiate with new type parameters in user code.
template<typename T> class PASCALIMPLEMENTATION MyTList__1 : public System::Generics::Collections::TList__1<T>
{
	typedef System::Generics::Collections::TList__1<T> inherited;
 
public:
	__fastcall MyTList__1(void);
	__fastcall virtual ~MyTList__1(void);
	static void __fastcall Cleanup(MyTList__1<T>* &L);
};
 
 
class DELPHICLASS DoubleList;
class PASCALIMPLEMENTATION DoubleList : public MyTList__1<double>
{
	typedef MyTList__1<double> inherited;
 
public:
	/* {DelphiUnit}MyTList<System_Double>.Create */ inline __fastcall DoubleList(void) : MyTList__1<double>() { }
	/* {DelphiUnit}MyTList<System_Double>.Destroy */ inline __fastcall virtual ~DoubleList(void) { }
 
};
 
 
class DELPHICLASS StringList;
class PASCALIMPLEMENTATION StringList : public MyTList__1<System::UnicodeString>
{
	typedef MyTList__1<System::UnicodeString> inherited;
 
public:
	/* {DelphiUnit}MyTList<System_string>.Create */ inline __fastcall StringList(void) : MyTList__1<System::UnicodeString>() { }
	/* {DelphiUnit}MyTList<System_string>.Destroy */ inline __fastcall virtual ~StringList(void) { }
 
};
 
 
//-- var, const, procedure ---------------------------------------------------
}	/* namespace Delphiunit */
#if !defined(DELPHIHEADER_NO_IMPLICIT_NAMESPACE_USE) && !defined(NO_USING_NAMESPACE_DELPHIUNIT)
using namespace Delphiunit;
#endif
#pragma pack(pop)
#pragma option pop
 
#pragma delphiheader end.
//-- end unit ----------------------------------------------------------------
#endif	// DelphiunitHPP

C++ code linking with the .obj created from the above Delphi unit can use instances of MyTList__1<double> or MyTList__1<System::String>.

 
void UseDLists()
{
  // C++ code can use the Generics defined in Delphi directly
  // as long as the C++ code limits itself to types for which
  // the generic was instantiated on the Delphi side. For example,
  // since the Delphi Unit instantiates MyTList<String>
  // and MyTList<double> we can use these here.
  // However, if we try to use MyTList__1<char> we'll get
  // errors since the Delphi side did not instantiate
  // MyTList<AnsiChar>.
  MyTList__1<double>* dblList = new MyTList__1<double>();
  dblList->Add(1.0);
  dblList->Add(1.5);
  double d = dblList->Items[1];
#ifdef _WIN64
  delete dblList
#else
  MyTList__1<double>::Cleanup(dblList);
#endif
 
  MyTList__1<System::String> *strList = new MyTList__1<System::String>();
  strList->Add("First");
  strList->Add("Second");
  strList->Add("Third");
  assert(strList->Count == 3);
 
  System::String str = strList->Items[0];
  assert(str == "First");
  assert(strList->Items[1] == "Second");
  assert(strList->Items[2] == "Third");
 
  strList->Insert(0, "Inserted");
  assert(strList->Count == 4);
  assert(strList->Items[0] == "Inserted");
  assert(strList->Items[1] == "First");
 
  strList->Reverse();
  assert(strList->Items[0] == "Third");
  assert(strList->Items[1] == "Second");
  assert(strList->Items[2] == "First");
  assert(strList->Items[3] == "Inserted");
 
  assert(strList->Contains("Inserted"));
  assert(!strList->Contains("Not Inserted"));
 
  strList->Sort();
  strList->Remove("Inserted");
 
  assert(strList->Items[0] == "First");
  assert(strList->Items[1] == "Second");
  assert(strList->Items[2] == "Third");
 
#ifdef _WIN64
  delete strList;
#else
  MyTList__1<System::String>::Cleanup(strList);
#endif
}

If C++ code attempts to use a Delphi generic for types that were not instantiated in Delphi, you'll get errors at link time. For example, the following code attempts to use MyTList__1<char> when the Delphi code did not explicitly instantiate MyTList<AnsiChar>:

 
void UseListOfChar()
{
  MyTList__1<char>* charList = new MyTList__1<char>();
  charList->Add('a');
  // ...
}

While the code above compiles, the following errors are generated at link time:

 
[ilink32 Error] Error: Unresolved external 'Delphiunit::MyTList__1<char>::' referenced from CPPUNIT.OBJ
[ilink32 Error] Error: Unresolved external '__fastcall Delphiunit::MyTList__1<char>::MyTList__1<char>()' referenced from CPPUNIT.OBJ
[ilink32 Error] Error: Unresolved external '__fastcall System::Generics::Collections::TList__1<char>::Add(const const char)' referenced from CPPUNIT.OBJ
[ilink32 Error] Error: Unable to perform link

To eliminate the error, you have to make sure that the Delphi code uses the type MyTList<AnsiChar>.

TDictionary

http://docwiki.embarcadero.com/CodeExamples/Berlin/en/Generics_Collections_TDictionary_(Delphi)

字典

队列

TQueue
http://docwiki.embarcadero.com/Libraries/Berlin/en/System.Generics.Collections.TQueue
http://docwiki.embarcadero.com/CodeExamples/Berlin/en/Generics_Collections_TQueue_(Delphi)

http://docwiki.embarcadero.com/Libraries/Berlin/en/System.Generics.Collections

TArray    
TDictionary    
TEnumerable    
TEnumerator    
TList    
TObjectDictionary    
TObjectList    
TObjectQueue    
TObjectStack    
TQueue    
TStack    
TThreadedQueue    
TThreadList