进程间通信可以使用内存映射文件；

在dll中共享数据可以使用内存映射文件

{*******************************************************}
{                                                       }
{       内存映射文件                                    }
{                                                       }
{       版权所有 (C) 2010 zhaoh                         }
{                                                       }
{*******************************************************}

unit unMapfile;

interface
uses
Windows,
SysUtils;
type
EMapCreateError =class(Exception);
EMapViewError=class(Exception);
{ TMapFile }

TMapFile=class
private
    hMapFile:THANDLE;
    pMemeory:Pointer;
    procedure MapFile;
public

    {-------------------------------------------------------------------------------
过程名:    Create ，创建一个内存映射文件
作者:      Administrator
日期:      2010.01.27
参数:      Size:DWORD; 内存映射文件的大小
    Name:string; 映射文件大小
    FileHandle:THandle=INVALID_HANDLE_VALUE 文件句柄， 默认是内存映射文件，可以把文件映射到内存，
返回值:    无
-------------------------------------------------------------------------------}
    constructor Create(Size:DWORD; Name:string;FileHandle:THandle=INVALID_HANDLE_VALUE);overload;

    {-------------------------------------------------------------------------------
过程名:    Create 打开一个已经存在的内存映射文件
作者:      Administrator
日期:      2010.01.27
参数:      Name:string
返回值:    无
-------------------------------------------------------------------------------}
    constructor Create(Name:string); overload;
    destructor Destroy; override;
    property MemoryPointer:Pointer read pMemeory;
end;
implementation

{ TMapFile }

constructor TMapFile.Create(Size:DWORD; Name:string;FileHandle:THandle=INVALID_HANDLE_VALUE);
begin
inherited Create;
hMapFile:=CreateFileMapping(FileHandle,nil,PAGE_READWRITE,0,Size,PChar(Name));
if hMapFile=0 then
    raise EMapCreateError.Create('');
MapFile;
end;

constructor TMapFile.Create(Name: string);
begin
inherited Create;
if SameText(Name,'') then
     raise EMapCreateError.Create('');
hMapFile:=OpenFileMapping(FILE_MAP_ALL_ACCESS,False,PChar(Name));
if hMapFile=0 then
    raise EMapCreateError.Create('');
MapFile;
end;

destructor TMapFile.Destroy;
begin
if pMemeory <> nil then
    UnmapViewOfFile(pMemeory);
if hMapFile<>0 then
    CloseHandle(hMapFile);
inherited;
end;

procedure TMapFile.MapFile;
begin
pMemeory:=MapViewOfFile(hMapFile,FILE_MAP_ALL_ACCESS,0,0,0);
if pMemeory=nil then
begin
    raise   EMapViewError.Create('');
end;
end;

end.

使用方法

try

    tmf:=TMapFile.Create('光军之城');
except
    tmf:=TMapFile.Create(100,'光军之城');

end;