如何把C#中声明的DLL部分的语法改为PB?

C#中如下:
[DllImport("libxl.dll", CallingConvention=CallingConvention.Cdecl, CharSet=CharSet.Unicode)]
private static extern IntPtr xlBookAddSheet(IntPtr handle, string name, IntPtr initSheet);
我在PB中这样引用的:
public function ulong addsheet(ulong hwb,string sheetname,ulong sheetid) library "libxl.dll" alias for "xlBookAddSheetA"
但运行时报异常:
Specified argument type differs from required argument type at runtime in DLL function name
"指定的参数类型与动态链接库中的函数所需要的参数类型不一致"