dll中的函数传递结构体，报地址错误，请高手帮忙！

[缘中人]

第一部分：调用DLL
typedef __stdcall bool readicxx (char * para1,//参数1
char *para2, //参数2
char *para3, //参数3
strout &strret //引用值，
);
readicxx *pfreadicxx;
1.装载

String dllpath("a.dll");
DLLInst=LoadLibrary(dllpath.c_str());
if( DLLInst == NULL )
{
ShowMessage(""dll未找到");
return ;
}
pfreadicxx=(readicxx*)GetProcAddress(DLLInst,"readicxx");
if( pfreadicxx == NULL )
{
ShowMessage("医保环境初始化失败!函数readicxx未装载");
return ;
}v