怎么多个应用程序共享同一个dll中的对象

如何多个应用程序共享同一个dll中的对象！
例：
有两个应用分别为app1, app2, 他们都加载了同一个dll: sharelib.dll 。
在Sharelib.dll 中导出一个函数为 function GetListObj:TList; 返回一个list对象，也就是List的指针。函数内容大概为
----------
var
g_List:TList;

function GetListObj:TList; stdcall;
begin
//没有就创建
if not Assigned(g_List) then
g_List := TList.Create;

resutl := g_List;
end;
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这时app1 程序用这个dll函数GetListObj返回的List对象，使用List的add方法，app2程序中使用此函数得到的对应可以读取到app1中添加的内容。

如何能实现这个效果，请高手指教一下。我看到有VC中可以使用
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#pragma data_seg("Shared")
std::list <User_Info> SrvSockList;
std::list <User_Info>::iterator pSockList;
SOCKET m_Listensock=0;
HWND g_hWnd = NULL;
#pragma data_seg()
#pragma comment(linker, "/Section:Shared,rws")
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我想delphi也应该有办法的

------解决方案--------------------
用内存映射，下面是我写的一段代码给你参考。

Delphi(Pascal) code


{****************************************************************************}
{                                                                            }
{       SharedMem.pas
{       Comment:真正的实现了服务和应用程序共享内存
{                                                                            }
{****************************************************************************}

unit MsgSharedMem;

interface

uses
  Windows, Messages, SysUtils, Math;

const
  CSharedMemSize = 1024*1024*3;
  CSharedMemName = 'Global\FleetReportSharedMemorty';

  WM_CreateReport = WM_USER + 1001;         
  WM_EndReport = WM_USER + 1002;            
  CSocketEndTag = #13#10;

type
  //报表执行状态
  TReportState = (rsFinished, rsInexistent, rsWaiting, rsRunning, rsException, rsCanceled);
  TShareMem = record
    Handle: THandle;                           
    ReportID: Integer;                         
    ReportState: TReportState;                 
    ReportType: Integer;                          
    StatFile: array[0..1024*1024] of Char;     
    TestConfig: array[0..1024*1024] of Char;   
    MapFile: array[0..1024*100] of Char;       
    SiteData: array[0..1024*100] of Char;      
    DestFile: array[0..1024*2] of Char;        
    HintMsg: array[0..1024*3] of Char;         
  end;
  PShareMem = ^TShareMem;

  TPublicVars = class
  private
    FShareMem: PShareMem;
    FMapFile: THandle;
    procedure SetHandle(AValue: THandle);
    function GetHandle: THandle;
    procedure SetReportID(AValue: Integer);
    function GetReportID: Integer;
    procedure SetReportState(AValue: TReportState);
    function GetReportState: TReportState;
    procedure SetReportType(AValue: Integer);
    function GetReportType: Integer;
    procedure SetStatFile(AValue: string);
    function GetStatFile: string;
    procedure SetTestConfig(AValue: string);
    function GetTestConfig: string;
    procedure SetMapFile(AValue: string);
    function GetMapFile: string;
    procedure SetSiteData(AValue: string);
    function GetSiteData: string;
    procedure SetDestFile(AValue: string);
    function GetDestFile: string;
    procedure SetHintMsg(AValue: string);
    function GetHintMsg: string;
  public
    constructor Create(ANew: Boolean);
    destructor Destroy; override;
    property Memory: PShareMem read FShareMem;
    property Handle: THandle read GetHandle write SetHandle;
    property ReportID: Integer read GetReportID write SetReportID;
    property ReportState: TReportState read GetReportState write SetReportState;
    property ReportType: Integer read GetReportType write SetReportType;
    property StatFile: string read GetStatFile write SetStatFile;
    property TestConfig: string read GetTestConfig write SetTestConfig;
    property MapFile: string read GetMapFile write SetMapFile;
    property SiteData: string read GetSiteData write SetSiteData;
    property DestFile: string read GetDestFile write SetDestFile;
    property HintMsg: string read GetHintMsg write SetHintMsg;
  end;

implementation

{ TPublicVars }
resourcestring
  CouldNotMapViewOfFile = 'Could not map view of file.';

const
  SECURITY_NULL_SID_AUTHORITY = 0;
  SECURITY_WORLD_SID_AUTHORITY = 1;
  SECURITY_LOCAL_SID_AUTHORITY = 2;
  SECURITY_CREATOR_SID_AUTHORITY = 3;
  SECURITY_NT_AUTHORITY = 5;

  SECURITY_NULL_RID = 0;
  SECURITY_WORLD_RID = 0;
  SECURITY_LOCAL_RID = 0;
  SECURITY_CREATOR_OWNER_RID = 0;
  SECURITY_CREATOR_GROUP_RID = 1;

  ACL_REVISION = 2; 

type
  ACL_SIZE_INFORMATION = record
    AceCount: DWORD;
    AclBytesInUse: DWORD;
    AclBytesFree: DWORD;
  end;

  ACE_HEADER = record
    AceType: BYTE;
    AceFlags: BYTE;
    AceSize: WORD;
  end;
  PACE_HEADER = ^ACE_HEADER;

  ACCESS_ALLOWED_ACE = record
    Header: ACE_HEADER;
    Mask: ACCESS_MASK;
    SidStart: DWORD;
  end;          

constructor TPublicVars.Create(ANew: Boolean);
var
  SecMem: SECURITY_ATTRIBUTES;
  aSD: SECURITY_DESCRIPTOR;
begin
  inherited Create;
  { 创建一个任何用户都可以访问的内核对象访问权 }
  InitializeSecurityDescriptor(@aSD, SECURITY_DESCRIPTOR_REVISION);
  SetSecurityDescriptorDacl(@aSD, True, nil, False);
  SecMem.nLength := SizeOf(SECURITY_ATTRIBUTES);
  SecMem.lpSecurityDescriptor := @aSD;
  SecMem.bInheritHandle := False;
  FMapFile := CreateFileMapping($FFFFFFFF, @SecMem, PAGE_READWRITE, 0, CSharedMemSize, CSharedMemName);
  FMapFile := OpenFileMapping(File_Map_All_Access, False, CSharedMemName);
  if (FMapFile = 0) then
  begin
    raise Exception.Create(SysErrorMessage(GetLastError));
    OutputDebugString(PChar(SysErrorMessage(GetLastError)));
  end
  else
  begin                                   // 成功
    FShareMem := MapViewOfFile(FMapFile, File_Map_All_Access, 0, 0, CSharedMemSize);
    OutputDebugString(PChar(SysErrorMessage(GetLastError) + ',Handle=' + IntToStr(Handle)));
  end;
end;

怎么多个应用程序共享同一个dll中的对象

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