C++ Msi函数判断应用是否已经安装

#include <Windows.h>
#include <Msi.h>
#pragma comment(lib, "Msi.lib")  

bool CheckExistSoftware(wchar_t *upgradeCode)  //可以通过工具Orca查看安装包相应的upgradeCode
{
    wchar_t productCode[39];
    if (ERROR_SUCCESS == MsiEnumRelatedProductsW(upgradeCode, 0, 0, productCode))
    {
        return true;
    }
    return false;
}  

void GetSoftwareInstallPath(const wchar_t *upgradeCode, wchar_t *installPath, DWORD *pathLength)
{
    DWORD i = 0;
    UINT result;
    wchar_t productCode[39];
    for (i = 0; ERROR_NO_MORE_ITEMS != (result = MsiEnumRelatedProductsW(upgradeCode, 0, i, productCode)); i++)
    {
        if (ERROR_SUCCESS == result)
        {
            if (ERROR_SUCCESS == MsiGetProductInfoW(productCode, INSTALLPROPERTY_INSTALLLOCATION, installPath, pathLength))
            {
                return;
            }
        }
    }
    wcscpy_s(installPath, 2, L"");
}