這是我寫的DLL源碼 以下是源碼除錯的時候跑出 

[BCC32 Warning] File2.cpp(64): W8066 Unreachable code




第64行是 DllMyForm2 = new TForm3(Application);
[code cpp]
//---------------------------------------------------------------------------
#include
#include
#pragma hdrstop
#include "Unit3.h" // TDllFrm 定义
//---------------------------------------------------------------------------
// Important note about DLL memory management when your DLL uses the
// static version of the RunTime Library:
//
// If your DLL exports any functions that pass String objects (or structs/
// classes containing nested Strings) as parameter or function results,
// you will need to add the library MEMMGR.LIB to both the DLL project and
// any other projects that use the DLL. You will also need to use MEMMGR.LIB
// if any other projects which use the DLL will be performing new or delete
// operations on any non-TObject-derived classes which are exported from the
// DLL. Adding MEMMGR.LIB to your project will change the DLL and its calling
// EXE's to use the BORLNDMM.DLL as their memory manager. In these cases,
// the file BORLNDMM.DLL should be deployed along with your DLL.
//
// To avoid using BORLNDMM.DLL, pass string information using "char *" or
// ShortString parameters.
//
// If your DLL uses the dynamic version of the RTL, you do not need to
// explicitly add MEMMGR.LIB as this will be done implicitly for you
//---------------------------------------------------------------------------

USERES("File.res");
USEFORM("Unit3.cpp", DllFrm);
//class __declspec(dllexport) __stdcall MyDllClass { //导出类
// public:
// MyDllClass();
// void CreateAForm();
// / / TForm3* DllMyForm;
//};
TForm3* DllMyForm2 ;

//---------------------------------------------------------------------------
BOOL APIENTRY DllMain( HMODULE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)

{
switch (ul_reason_for_call)
{
/*case DLL_PROCESS_ATTACH:
break;
case DLL_THREAD_ATTACH:
case DLL_THREAD_DETACH:
case DLL_PROCESS_DETACH:
*/
TForm3* DllMyForm2 ;
DllMyForm2 = new TForm3(Application);
DllMyForm2->Show();
ShowMessage("0");
ShowMessage("1");
ShowMessage("0");
ShowMessage("0");
ShowMessage("0");
ShowMessage("0");
break;
}
return TRUE;
}
//---------------------------------------------------------------------------

//---------------------------------------------------------------------------
void __stdcall CreateFromFunct()
{
DllMyForm2 = new TForm3(Application);
DllMyForm2->Show();
}


[/code]

編輯記錄

form 是宣告在 DLL 中的嗎?
如果是的話, 在 DLL 中沒有 Application, 這個系統物件只有在 EXE 中才存在.

建議可以把參數換成 nil , 或是要重新取得 application 的 handle.

------
水瓶男的blog: http://791909.blogspot.com

1.
第64行是 DllMyForm2 = new TForm3(Application); 有兩行

2.
只是警告你那一行，永遠執行不到 (你沒有 Export)

===================引 用 guardian635 文 章===================
這是我寫的DLL源碼 以下是源碼除錯的時候跑出

[BCC32 Warning] File2.cpp(64): W8066 Unreachable code




第64行是 DllMyForm2 = new TForm3(Application);
[code cpp]
//---------------------------------------------------------------------------
#include
#include
#pragma hdrstop
#include "Unit3.h" // TDllFrm 定义
//---------------------------------------------------------------------------
// Important note about DLL memory management when your DLL uses the
// static version of the RunTime Library:
//
// If your DLL exports any functions that pass String objects (or structs/
// classes containing nested Strings) as parameter or function results,
// you will need to add the library MEMMGR.LIB to both the DLL project and
// any other projects that use the DLL. You will also need to use MEMMGR.LIB
// if any other projects which use the DLL will be performing new or delete
// operations on any non-TObject-derived classes which are exported from the
// DLL. Adding MEMMGR.LIB to your project will change the DLL and its calling
// EXE's to use the BORLNDMM.DLL as their memory manager. In these cases,
// the file BORLNDMM.DLL should be deployed along with your DLL.
//
// To avoid using BORLNDMM.DLL, pass string information using "char *" or
// ShortString parameters.
//
// If your DLL uses the dynamic version of the RTL, you do not need to
// explicitly add MEMMGR.LIB as this will be done implicitly for you
//---------------------------------------------------------------------------

USERES("File.res");
USEFORM("Unit3.cpp", DllFrm);
//class __declspec(dllexport) __stdcall MyDllClass { //导出类
// public:
// MyDllClass();
// void CreateAForm();
/// / TForm3* DllMyForm;
//};
TForm3* DllMyForm2 ;

//---------------------------------------------------------------------------
BOOL APIENTRY DllMain( HMODULE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)

{
switch (ul_reason_for_call)
{
/*case DLL_PROCESS_ATTACH:
break;
case DLL_THREAD_ATTACH:
case DLL_THREAD_DETACH:
case DLL_PROCESS_DETACH:
*/
TForm3* DllMyForm2 ;
DllMyForm2 = new TForm3(Application);
DllMyForm2->Show();
ShowMessage("0");
ShowMessage("1");
ShowMessage("0");
ShowMessage("0");
ShowMessage("0");
ShowMessage("0");
break;
}
return TRUE;
}
//---------------------------------------------------------------------------

//---------------------------------------------------------------------------
void __stdcall CreateFromFunct()
{
DllMyForm2= new TForm3(Application);
DllMyForm2->Show();
}


[/code]