Google API throws exception at specified lat & long position? - c#-4.0

Question

Below is my sample code
public static string GetGeoLoc(string latitude, string longitude,
out string Address_ShortCountryName,
out string Address_country,
out string Address_administrative_area_level_1,
out string Address_administrative_area_level_1_short_name,
out string Address_administrative_area_level_2,
out string Address_administrative_area_level_3,
out string Address_colloquial_area,
out string Address_locality,
out string Address_sublocality,
out string Address_neighborhood)
{
Address_ShortCountryName = "";
Address_country = "";
Address_administrative_area_level_1 = "";
Address_administrative_area_level_1_short_name = "";
Address_administrative_area_level_2 = "";
Address_administrative_area_level_3 = "";
Address_colloquial_area = "";
Address_locality = "";
Address_sublocality = "";
Address_neighborhood = "";
XmlDocument doc = new XmlDocument();
try
{
doc.Load("http://maps.googleapis.com/maps/api/geocode/xml?latlng=" + latitude + "," + longitude + "&sensor=false");
XmlNode element = doc.SelectSingleNode("//GeocodeResponse/status");
if (element.InnerText == "ZERO_RESULTS")
{
return ("No data available for the specified location");
}
else
{
element = doc.SelectSingleNode("//GeocodeResponse/result/formatted_address");
string longname = "";
string shortname = "";
string typename = "";
XmlNodeList xnList = doc.SelectNodes("//GeocodeResponse/result/address_component");
foreach (XmlNode xn in xnList)
{
try
{
longname = xn["long_name"].InnerText;
shortname = xn["short_name"].InnerText;
typename = xn["type"].InnerText;
switch (typename)
{
case "country":
{
Address_country = longname;
Address_ShortCountryName = shortname;
break;
}
case "locality":
{
Address_locality = longname;
break;
}
case "sublocality":
{
Address_sublocality = longname;
break;
}
case "neighborhood":
{
Address_neighborhood = longname;
break;
}
case "colloquial_area":
{
Address_colloquial_area = longname;
break;
}
case "administrative_area_level_1":
{
Address_administrative_area_level_1 = longname;
Address_administrative_area_level_1_short_name = shortname;
break;
}
case "administrative_area_level_2":
{
Address_administrative_area_level_2 = longname;
break;
}
case "administrative_area_level_3":
{
Address_administrative_area_level_3 = longname;
break;
}
default:
break;
}
}
catch (Exception e)
{
clsExHandler.Instance.Write(e);
}
}
return (element.InnerText);
}
}
catch (Exception ex)
{
return ("(Address lookup failed: ) " + ex.Message);
}
}
try passing latitude as 33.4965 & longitude as -112.205
i'm getting an exception object reference to invalid object in the line
**typename = xn["type"].InnerText;**
when i debug step by step there is no such attribute like ["type"]
Also there are some other lingual character why?
How could i resolve this issue.

Answer 1

I'm not familiar with c# and Im not sure if your code is correct at all(e.g. types is not an attribute, it's an elementNode).
Assuming that your code is correct and you can select nodes by using node['nameOfChildNode'] , when you inspect the XML-File: http://maps.googleapis.com/maps/api/geocode/xml?latlng=33.4965,-112.205&sensor=false you will see that there are address_components with 2 <type>'s and also address_components without any <type> .
I guess your code breaks not at the missing <type>, it breaks when you try to access a property(InnerText) of the missing <type>.
What you can do: use selectSingleNode to select the <type> and when it returns null implement a fallback or leave the further processing.

Answer 2

http://maps.googleapis.com/maps/api/geocode/json?latlng=33.4965%20,%20-112.205&sensor=false
returns
{
"results" : [],
"status" : "ZERO_RESULTS"
}
Therefore
XmlNode element = doc.SelectSingleNode("//GeocodeResponse/status");
if (element.InnerText == "ZERO_RESULTS")
{
return ("No data available for the specified location");
}
is not catching ZERO_RESULTS.
I am not familiar with C# so I cannot help further.