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How Do I Use C# To Read XML Sub Elements

Hello.
I am having a problem trying to read sub elements in an XML document. Here is a simple example of the XML document I am currently able to read:

<?xml version="1.0" encoding="utf-8"?>
<WorkTeams>
<WorkTeam Name="BlueTeam">
<HomeBase>Los Angeles</HomeBase>
<Vehicles>35</Vehicles>
</WorkTeam>
<WorkTeam Name="RedTeam">
<HomeBase>San Diego</HomeBase>
<Vehicles>20</Vehicles>
</WorkTeam>
</WorkTeams>

I am able to read the above simple XML document with the following c# code:

private void ReadXMLVehicleInfo()
{
String HomeBase = "";
String Vehicles = "";

DataSet ds = new DataSet();
ds.ReadXml("c:\\VehicleTeams.xml");

DataRow[] drs = ds.Tables["WorkTeam"].Select("Name = 'BlueTeam' ");
if (drs.Length != 0)
{
HomeBase = drs[0]["HomeBase"].ToString();
Vehicles = drs[0]["Vehicles"].ToString();
}
else
{
}
}

My problem begins when I tried to introduce an element, (VehicleMfgs), with sub elements, (VehicleMfg),such as in the following XML document:

<?xml version="1.0" encoding="utf-8"?>
<WorkTeams>
<WorkTeam Name="BlueTeam">
<HomeBase>Los Angeles</HomeBase>
<Vehicles>35</Vehicles>
<VehicleMfgs>
<VehicleMfg>Toyota</VehicleMfg>
<VehicleMfg>Nissan</VehicleMfg>
<VehicleMfg>Volvo</VehicleMfg>
</VehicleMfgs>
</WorkTeam>
<WorkTeam Name="RedTeam">
<HomeBase>San Diego</HomeBase>
<Vehicles>20</Vehicles>
<VehicleMfgs>
<VehicleMfg>Ford</VehicleMfg>
<VehicleMfg>Dodge</VehicleMfg>
<VehicleMfg>Suzuki</VehicleMfg>
</VehicleMfgs>
</WorkTeam>
</WorkTeams>

How do I get a collection or list of the VehcleMfgs given that I know table will be WorkTeam and Name will be RedTeam? The above code approach does not handle sub lists like the the one above with 3 different vehicle mfgs (i.e. Ford, Dodge, Suzuki). Perhaps I should not be using a dataset or datatable. Please advise if there is another way to do this with not much effort but while still using .NET XML classes.
Thanks in advance.

Alexandre Simões

Where did the XML came from?
Why are you creating it's schema by hand?

The easiest way to do this is to create a type dataset with your schema. Fill the dataset with your data and serialize it (WriteXML). Reading it is as easy as ds.ReadXML.

What you're doing right now isn't a dataset, it's nested classes...
A colletion of a class WorkTeams that have 3 public properties:
HomeBase (string)
Vehicles (int)
VehicleMfgs that is a collection of a class VehicleMfg.

So, or you use the XMLReader to loop through the nodes or you create a class hierarchy to map your structure... yet, I think it's much easier to use the dataset directly.

zonkerman

ASKER

Hello AlexCode.
The XML is created by a c# utility that performs something like the following:

private void WriteXMLConfigInfo()
{
XmlWriterSettings settings = new XmlWriterSettings();
settings.Indent = true;
settings.IndentChars = (" ");
XmlWriter writer = XmlWriter.Create("c:\\VehicleTeams.xml", settings);
// Write XML data.

//Use automatic indentation for readability.
// writer.Formatting = Formatting.Indented;

//Write the XML delcaration.
writer.WriteStartDocument();

//Write the root element
writer.WriteStartElement("WorkTeams");

//Start an element
writer.WriteStartElement("WorkTeam");

//Add an attribute to the previously created element
writer.WriteAttributeString("Name", "BlueTeam");

//add sub-elements
writer.WriteElementString("HomeBase", "Los Angeles");
writer.WriteElementString("Vehicles", "35");
.......

The utility provides a gui for a user to setup information needed by an application. I need for the user to create the necessary information with a gui rather than expect them to edit an xml file by hand. The utility works fine so far but now I need to deal with a list of sub elements as I described in the first note. I have used an XMLReader before but I am looking for a way to directly access the section of the XML file rather than have to iterate through checking for the right area. That is why I was using the instance of a Dataset class followed by an instance collection of DataRow class so I could use the "select" filter ability. I'm sure this could be done with LINQ but I won't be up to speed on LINQ for a while. So I am seeking a way to have my C# code jump the the relevant area of the XML document then extract the information that pertains to that section (data row) for a given team name.

zonkerman

ASKER

For now I have found that if I change the XML format to the following then the original C# code I have will handle the list of vehicle manufacturers:

<?xml version="1.0" encoding="utf-8"?>
<WorkTeams>
<WorkTeam Name="BlueTeam">
<HomeBase>Los Angeles</HomeBase>
<Vehicles>35</Vehicles>
<VehicleMfgs>Toyota,Nissan,Volvo</VehicleMfg>
</WorkTeam>
<WorkTeam Name="RedTeam">
<HomeBase>San Diego</HomeBase>
<Vehicles>20</Vehicles>
<VehicleMfgs>Ford,Dodge,Suzuki</VehicleMfgs>
</WorkTeam>
</WorkTeams>

Unfortunately with the new format I have to parse out the list of vehicle manufacturers which are now delimited by commas rather than listed as separate elements as before. If anyone can provide a way to access the VehicleMfgs as I had listed in the first example which was as follows:
<VehicleMfgs>
<VehicleMfg>Ford</VehicleMfg>
<VehicleMfg>Dodge</VehicleMfg>
<VehicleMfg>Suzuki</VehicleMfg>
</VehicleMfgs>

then please provide an example of how it can be done. Thanks in advance.

ASKER CERTIFIED SOLUTION

joechina

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zonkerman

ASKER

Hello joechina.
Thank you for your solution. Your sample code is direct, to the point, and exactly what I was looking for. Good Job!

zonkerman

ASKER

Thanks joechina. Your solution is direct, to the point, and exactly what I was hoping for. Good Job!