Parse particular text from an XML string

Question

Im writing an app which reads an RSS feed and places items on a map. I need to read the lat and long numbers only from this string: http://www.digitalvision.se/feed.aspx?isAlert=true&lat=53.647351&lon=-1.933506 .This is contained in link tags

Im a bit of a programming noob but im writing this in C#/Silverlight using Linq to XML.

Shold this text be extrated when parsing or after parsing and sent to a class to do this? Many thanks for your assistance.

EDIT. Im going to try and do a regex on this

this is where I need to integrate the regex somewhere in this code. I need to take the lat and long from the Link element and seperate it into two variables I can use (the results are part of a foreach loop that creates a list.)

  var events = from ev in document.Descendants("item")
                     select new
                     {
                         Title = (ev.Element("title").Value),
                         Description = (ev.Element("description").Value),
                         Link = (ev.Element("link").Value),
                     };

Question is im not quite sure where to put the regex (once I work out how to use the regex properly! :-) )

Answer 1

try this

var url = "http://www.xxxxxxxxxxxxxx.co.uk/map.aspx?isTrafficAlert=true&lat=53.647351&lon=-1.93350";
var items = url.Split('?')[1]
    .Split('&')
    .Select(i => i.Split('='))
    .ToDictionary(o => o[0], o => o[1]);
var lon = items["lon"];
var lat = items["lat"];

Answer 2

If you only need the Lat and Lon values and the feed is just one big XML string you can do the whole thing with a regular expression.

var rssFeed = @"http://www.xxxxxxxxxxxxxx.co.uk/map.aspx?isTrafficAlert=true&lat=53.647351&lon=-1.933506 
                http://www.xxxxxxxxxxxxxx.co.uk/map.aspx?isTrafficAlert=true&lat=53.647352&lon=-1.933507 
                http://www.xxxxxxxxxxxxxx.co.uk/map.aspx?isTrafficAlert=true&lat=53.647353&lon=-1.933508 
                http://www.xxxxxxxxxxxxxx.co.uk/map.aspx?isTrafficAlert=true&lat=53.647354&lon=-1.933509";

var regex = new Regex(@"lat=(?<Lat>[+-]?\d*\.\d*)&lon=(?<Lon>[+-]?\d*\.\d*)");

var latLongPairs = new List<Tuple<decimal, decimal>>();

foreach (Match match in regex.Matches(rssFeed))
{
    var lat = Convert.ToDecimal(match.Groups["Lat"].Value);
    var lon = Convert.ToDecimal(match.Groups["Lon"].Value);
    latLongPairs.Add(new Tuple<decimal, decimal>(lat, lon));
}