Read xml lines from url - c++

Question

I want to read xml lines from an internet url( url will be input) and extract the date value( dd,mm,yyyy) to a string or int. How can I do that using visual c++,mfc in an efficient way ?
The lines available on the web page are as shown below.
thanks.
<location>
<latitude>0</latitude>
<longitude>0</longitude>
</location>
<offset>0</offset>
<suffix>Z</suffix>
<localtime>11 Nov 2013 15:23:58</localtime>
<isotime>2013-11-11 15:23:58 +0000</isotime>
<utctime>2013-11-11 15:23:58</utctime>
<dst>False</dst>

Answer 1

Thank you guys for your all comments. I searched and used cURL library to overcome my issue.Possibly the easiest way with some examples. Also thanks to previous topic, it helped a lot: How do I download xml from the internet in C++
size_t AppendDataToStringCurlCallback(void *ptr, size_t size, size_t nmemb, void *vstring)
{
std::string * pstring = (std::string*)vstring;
pstring->append((char*)ptr, size * nmemb);
return size * nmemb;
}
std::string DownloadUrlAsString(const std::string & url)
{
std::string body;
CURL *curl_handle;
curl_global_init(CURL_GLOBAL_ALL);
curl_handle = curl_easy_init();
curl_easy_setopt(curl_handle, CURLOPT_URL, url.c_str());
curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, AppendDataToStringCurlCallback);
curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, &body);
curl_easy_perform(curl_handle);
curl_easy_cleanup(curl_handle);
return body;
}
int main(void)
{
CURL *curl;
CURLcode res;
std::string data_to_read;
curl = curl_easy_init();
if(curl) {
//curl_easy_setopt(curl, CURLOPT_URL, "www.earthtools.org/timezone/0/0");
data_to_read=DownloadUrlAsString("www.earthtools.org/timezone/0/0");
res = curl_easy_perform(curl);
// always cleanup
curl_easy_cleanup(curl);
}
std::string str=data_to_read;
std::string str2 ("<utctime>");
std::size_t found = str.find(str2);
if (found!=std::string::npos)
std::cout << "first data found at: " << found << '\n';
//data_to_read[found+9]
char year[4];//="yyyy";
char month[2];//="mm";
char day[2];//="dd";
int delta=0;
int start=found+9;
for (int k=start; k<start+10;k++)
{
if(k<start+4){
year[delta]= data_to_read[k];
delta++;
}
else if (k==start+4)
delta=0;
else if ((k>=start+5) && (k<=start+6))
{
month[delta]=data_to_read[k];
delta++;
}
else if (k==start+7)
delta=0;
else if ((k>=start+8) && (k<=start+9))
{
day[delta]=data_to_read[k];
delta++;
}
}
int year_m=atoi(year);
int month_m=atoi(month);
int day_m=atoi(day);

Answer 2

Use IXMLHTTPRequest object to download the content.
Once downloaded, the object's responseXML property returns IXMLDOMDocument pointer representing the parsed XML document.
Use its selectNodes or selectSingleNode methods to locate the desired node, as represented by IXMLDOMNode interface.
Read its nodeValue property to get the text it contains.
InternetTimeToSystemTime could be used to parse the string like "11 Nov 2013 15:23:58". I can't think, off the top of my head, of a ready-made function to parse an ISO date like "2013-11-11 15:23:58", but it seems amenable to a plain old sscanf.