那位用过RasGetEntryProperties和RasSetEntryProperties两个函数？帮忙看看我的代码错在那里了？

#include "Ras.h"

typedef DWORD(*RASGETPRO)(LPCTSTR,LPCTSTR,LPRASENTRY,LPDWORD,LPBYTE,LPDWORD);

RASENTRY Info = {0};
DWORD dwSize,dwDevInfo,code;

dwSize = Info.dwSize = sizeof(RASENTRY);
dwDevInfo = 0;

HINSTANCE hinstLib;
RASGETPRO hsRasGetEntryProperties;
BOOL FreeSuccess,RunTimeLinkSuccess = FALSE;

hinstLib = LoadLibrary("Rasapi32");
if (NULL != hinstLib)
{
hsRasGetEntryProperties = (RASGETPRO)GetProcAddress(hinstLib,"RasGetEntryProperties");
if (NULL != hsRasGetEntryProperties)
{
RunTimeLinkSuccess = TRUE;
//--------------------------------------------------------------
RASENTRY *pRasEntry;
DWORD dw=0;
DWORD ret = (hsRasGetEntryProperties)(NULL, "GPRS", NULL, &dw, NULL, NULL);
// (hsRasGetEntryProperties)(NULL, "GPRS", NULL, &dw, NULL, NULL);
// if(ret == ERROR_BUFFER_TOO_SMALL)
// {
pRasEntry=(RASENTRY *)HeapAlloc(GetProcessHeap(),0,dw);
pRasEntry->dwSize = sizeof(RASENTRY);;
// ret = (hsRasGetEntryProperties)(NULL, "GPRS", pRasEntry, &dw, NULL, NULL);
// if(ret!=NULL)
// {
// GetRasErr(ret);
// return 0;
// }
// }

//--------------------------------------------------------------

}
FreeSuccess = FreeLibrary(hinstLib);
}
else
{
AfxMessageBox("加载DLL失败！");
}
if ( ! RunTimeLinkSuccess )
{
AfxMessageBox("不能确定对应函数地址！");
}


注释部分一放开更是错误重重。现在是运行到DWORD ret = (hsRasGetEntryProperties)(NULL, "GPRS", NULL, &dw, NULL, NULL);这句就出错。



另外我加载自己的测试DLL，却没问题，看来问题出在函数参数设置上，有谁调用过RasGetEntryProperties，和RasSetEntryProperties函数的？请帮忙指点一下。谢谢~！

DLL的CPP中：
int hytestdll( int x )
{
int i=0;
i=x+1;
return i;
}

DLL的DEF中：
LIBRARY FINGER
EXPORTS
………………
hytestdll @4


应用程序的CPP中：
typedef int (*TESTDLLFUN)( int );

HINSTANCE hinstLib;
TESTDLLFUN testdllfunhy;
BOOL FreeSuccess,RunTimeLinkSuccess = FALSE;
int i=5;

hinstLib = LoadLibrary("UserHsRasDll2");
if (NULL != hinstLib)
{
testdllfunhy = (TESTDLLFUN)GetProcAddress(hinstLib,"hytestdll");
if (NULL != testdllfunhy)
{
RunTimeLinkSuccess = TRUE;
i = (testdllfunhy)(i);
switch (i)
{
case 6:
AfxMessageBox("调用成功！");
break;
case 5:
AfxMessageBox("调用失败！");
break;
}
}
FreeSuccess = FreeLibrary(hinstLib);
}
else
{
AfxMessageBox("加载DLL失败！");
}
if ( ! RunTimeLinkSuccess )
{
AfxMessageBox("不能确定对应函数地址！");
}

这是我写的小测试代码，已经在WIN98，VC6下通过