WinHttpCrackUrl failed with 87 error - c++

Question

URL_COMPONENTS urlComp;
LPCWSTR pwszUrl1 =
L"http://search.msn.com/results.asp?RS=CHECKED&FORM=MSNH&v=1&q=wininet";
DWORD dwUrlLen = 0;
// Initialize the URL_COMPONENTS structure.
ZeroMemory(&urlComp, sizeof(urlComp));
urlComp.dwStructSize = sizeof(urlComp);
// Set required component lengths to non-zero
// so that they are cracked.
urlComp.dwSchemeLength = (DWORD)-1;
urlComp.dwHostNameLength = (DWORD)-1;
urlComp.dwUrlPathLength = (DWORD)-1;
urlComp.dwExtraInfoLength = (DWORD)-1;
// Crack the URL.
if (!WinHttpCrackUrl( pwszUrl1, (DWORD)wcslen(pwszUrl1), 0, &urlComp))
{
printf("Error %u in WinHttpCrackUrl.\n", GetLastError());
}
This WinHttpCrackUrl api failed with 87(invalid param) on Win7( OS ) please any one suggest a solution or how can i decode my URL in an Easy way in server side ?.Also i want to know how can i distinguish %20 from encoded URL and actual data present in the URL. Example: localhost:8080\Server\search?value="value%20"

Answer 1

Sets required component lengths to expected value.
All to zero if doesn't need to crack.
urlComp.dwSchemeLength = (DWORD)0;
urlComp.dwHostNameLength = (DWORD)0;
urlComp.dwUrlPathLength = (DWORD)0;
urlComp.dwExtraInfoLength = (DWORD)0;
Or
std::wstring urlHost;
urlHost.resize(url.size());
urlComp.dwHostNameLength = (DWORD)urlHost.size();
urlComp.lpszHostName = &urlHost[0];