XML format enforcement

[Sharon]

I wish to write some kind of XML format enforcer like DTD, XSD or other that
can do the following:
(1) Any element and node must have Type attribute that can be read as data
type by the parser.
(1) Any element and node may have (optional) four more attributes.

I XML enforcer should allow any tree structure and any number of nodes in
any tree.

Does anyone can tell how it's possible?

Any example will be most appreciated.
--
Thanks
Sharon

[Martin Honnen]

Sharon wrote:

I wish to write some kind of XML format enforcer like DTD, XSD or other that
can do the following:
(1) Any element and node must have Type attribute that can be read as data
type by the parser.

If you use the W3C XSD schema language the you can use the predefined
xsi:type
attribute although usually it suffices to defined the types in the
schema and validate against that schema, there is no need in that case
to have the type in the XML instance document.

--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[Sharon]

Thanks Martin for your reply.
I'm not sure I fully understand you.

Should I use XSD?
How can I validate the four other attributes?

Can you post me some kind of example?
--
Thanks
Sharon

[Sharon]

Ok, I think I found a way to do thanks to Marc Clifton articale on
CodeProject (http://www.codeproject.com/dotnet/MycroXaml.asp).

The XML file can be somthing like that:

<?xml version="1.0" encoding="utf-8"?>
<System Name="System">
<Paramaters>
<Speed type="System.Iint32">111</Speed >
<_xAxis type="System.Single">222</_xAxis>
<_yAxis type="System.Double">333</_yAxis>
<_ID type="System.Int64">444</_ID>
<_Name type="System.String">String value...</_Name>
</Paramaters>
</System>
And the C# code can be:

System.IO.StreamReader sr = new System.IO.StreamReader("TypesDef.xml");
string text = sr.ReadToEnd();
sr.Close();
XmlDocument doc = new XmlDocument();
doc.LoadXml(text);
XmlNode node = doc.FirstChild;
while( node.NodeType.ToString() != "Element" )
{
node = node.NextSibling;
}

XmlNode paramsNode = doc.SelectSingleNode("//Paramaters");
XmlNodeList nodeList = paramsNode.ChildNodes;
Hashtable verTypes = new Hashtable(nodeList.Count);
string typeName = "";
Type type;

foreach( XmlNode xmlNode in nodeList )
{
XmlAttribute attr = xmlNode.Attributes["type"];
typeName = attr.Value;
if( typeName == "System.String" )
{
verTypes[xmlNode.Name] = xmlNode.InnerText;
}
else
{
type = Type.GetType(typeName, false);
object typeIntance = Activator.CreateInstance(type);
System.Reflection.MethodInfo Parse = type.GetMethod("Parse", new Type
[] {typeof(String)});
verTypes[xmlNode.Name] = Parse.Invoke(type, new object[]
{xmlNode.InnerText});
}
}

------
Regards
Sharon