Search in XML

toanhoi bui

Hi,everybody.I have a xml file and I want to find coordinates of a place

Example I enter a string "Stop-bus".After,I use a function and I will find coordianates lat=21.007 lon="105.9988".Can you write a function or class to find ?Can you help me,please?

5 Replies

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Felipe Ramos16y ago
No problem, hope that helps.
toanhoi bui16y ago
Thanks you very much.
Felipe Ramos16y ago
Let me know if this helps, it is base on your sample xml. Other things you could do is call mapquest, yahoo, google geo webservices to get lat,lon for addresses.

   public struct Location
   {
   public int ID;
   public float Lat;
   public float Lon;
   }

   private Location Search(string place)
   {
   // In your code you may want to keep the xml in memory instead of loading it all the time.
   System.Xml.XmlDocument doc = new System.Xml.XmlDocument();
   doc.Load(System.IO.Directory.GetCurrentDirectory() + @"\Test.xml");

   System.Xml.XmlNode node =
   doc.SelectSingleNode(string.Format("//osm/node/tag[@k='name' and @v='{0}']", place)).ParentNode;

   return new Location()
   {
   ID = Convert.ToInt32(node.Attributes["id"].Value),
   Lat = Convert.ToSingle(node.Attributes["lat"].Value),
   Lon = Convert.ToSingle(node.Attributes["lon"].Value)
   };
   }

// Sample call
  Location loc = Search("Stop-bus");
toanhoi bui16y ago
Thanks you for Reply,But I want to get coordinates of the place.What command should I use?Can you help me?I want to write a function to search a place.The function is construct of Search(string nameplace){...}.And if I use the function ,I will have got coordinates of the palce.Can you write the function ?Thanks you very much?
Felipe Ramos16y ago
Here is one way to do it. You can load the file into an XMLDocument object

System.Xml.XmlDocument doc = new System.Xml.XmlDocument();
doc.Load(System.IO.Directory.GetCurrentDirectory() + @"\Test.xml");

--Thank you can use xpath to query the xml, you basically saying grab any tag node with the attribute k equaling name and v equaling Stop-bus and grab the parent node, in this case node. Than you can grab the attributes from the parent.
System.Xml.XmlNode node = doc.SelectSingleNode("//osm/node/tag[@k='name' and @v='Stop-bus']");