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Use TDictionary in C ++ Builder XE2

I currently want to use TDitionaryin C ++ Buillder XE2

After I read the documentation , I thought it should have been easy, but I can’t even create an object TDictionary...

My code is:

#include <vcl.h>
#pragma hdrstop
#include <Generics.collections.hpp>
#include "TDictionaryTest.h"

#pragma package(smart_init)
#pragma resource "*.dfm"
TForm2 *Form2;

void __fastcall TForm2::FormCreate(TObject *Sender)
{
    TDictionary__2 <String, String> *Dir = new  TDictionary__2<String, String>(0);
    delete Dir;
}

Error messages:

[ILINK32 Error] Error: Unresolved external '__fastcall           System::Generics::Collections::TDictionary__2<System::UnicodeString,   System::UnicodeString>::~TDictionary__2<System::UnicodeString, System::UnicodeString>()'  referenced from ...\PRACTICE\C++\WIN32\DEBUG\TDICTIONARYTEST.OBJ
[ILINK32 Error] Error: Unresolved external '__fastcall System::Generics::Collections::TEnumerable__1<System::Generics::Collections::TPair__2<System::UnicodeString, System::UnicodeString> >::~TEnumerable__1<System::Generics::Collections::TPair__2<System::UnicodeString, System::UnicodeString> >()' referenced from ...\PRACTICE\C++\WIN32\DEBUG\TDICTIONARYTEST.OBJ
[ILINK32 Error] Error: Unresolved external 'System::Generics::Collections::TDictionary__2<System::UnicodeString, System::UnicodeString>::' referenced from ...\PRACTICE\C++\WIN32\DEBUG\TDICTIONARYTEST.OBJ
[ILINK32 Error] Error: Unresolved external '__fastcall System::Generics::Collections::TDictionary__2<System::UnicodeString, System::UnicodeString>::TDictionary__2<System::UnicodeString, System::UnicodeString>(int)' referenced from ...\PRACTICE\C++\WIN32\DEBUG\TDICTIONARYTEST.OBJ
[ILINK32 Error] Error: Unable to perform link

Anyone have an idea? Thank!

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2 answers

Like @mhtaqia, C ++ cannot create Delphi Generics classes, but only consumes them when they are created by Delphi code. For C ++ code, you should use STL std::mapinstead:

#include <map> 

void __fastcall TForm2::FormCreate(TObject *Sender) 
{ 
    std::map<String, String> *Dir = new std::map<String, String>; 
    delete Dir; 
}

Or:

#include <map> 

void __fastcall TForm2::FormCreate(TObject *Sender) 
{ 
    std::map<String, String> Dir; 
}

: TForm::OnCreate TForm::OnDestroy ++. Delphi, ++, , . /.

+7

TDictionary Delphi. ++-. , .

+2

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