Remove a query string parameter from a URL

I have a URL in wstring format in C++, e.g.:

http://stackoverflow.com?Country=US&City=Seattle&State=WA

I want to get rid of Country query param from the above string. Country query param can be the first query param or could be the last too.

 wstring ManagementUrl = L"http://stackoverflow.com?Country=US&City=Seattle&State=WA"    wstring queryParam = L"&Country=US";    wstring queryParam1 = L"Country=US";    string::size_type urlLength = ManagementUrl.length();    string::size_type queryLength = queryParam.length();    string::size_type queryLength1 = queryParam1.length();    size_t index = ManagementUrl.find(queryParam);            if (index != std::wstring::npos)            {                wstrLink.erase(index, queryLength);            }        size_t index1 = ManagementUrl.find(queryParam1);            if (index != std::wstring::npos)            {                wstrLink.erase(index, queryLength1);            }  

Is there a better way to do this?