public void ResolveEntity2()
{
string ent1 = "<!ENTITY ent 'entity string'>";
string ent2 = "<!ENTITY ent2 '<foo/><foo/>'>]>";
string dtd = "<!DOCTYPE root[<!ELEMENT root (#PCDATA|foo)*>" + ent1 + ent2;
string xml = dtd + "<root>&ent3;&ent2;</root>";
dvr = new XmlValidatingReader(xml, XmlNodeType.Document, null);
dvr.ValidationType = ValidationType.None;
dvr.EntityHandling = EntityHandling.ExpandCharEntities;
dvr.Read(); // DTD
dvr.Read(); // root
dvr.Read(); // &ent3;
Assert.AreEqual(XmlNodeType.EntityReference, dvr.NodeType);
#if NET_2_0
// under .NET 2.0, an error is raised here.
// under .NET 1.1, the error is thrown on the next read.
try {
dvr.ResolveEntity();
Assert.Fail("Attempt to resolve undeclared entity should fail.");
} catch (XmlException) {
}
#else
// ent3 does not exist in this dtd.
dvr.ResolveEntity();
Assert.AreEqual(XmlNodeType.EntityReference, dvr.NodeType);
try {
dvr.Read();
Assert.Fail("Attempt to resolve undeclared entity should fail.");
} catch (XmlException) {
}
#endif
}
public void ResolveEntity()
{
string ent1 = "<!ENTITY ent 'entity string'>";
string ent2 = "<!ENTITY ent2 '<foo/><foo/>'>]>";
string dtd = "<!DOCTYPE root[<!ELEMENT root (#PCDATA|foo)*>" + ent1 + ent2;
string xml = dtd + "<root>&ent;&ent2;</root>";
dvr = new XmlValidatingReader(xml, XmlNodeType.Document, null);
dvr.ValidationType = ValidationType.None;
dvr.EntityHandling = EntityHandling.ExpandCharEntities;
dvr.Read(); // DTD
dvr.Read(); // root
dvr.Read(); // &ent;
Assert.AreEqual(XmlNodeType.EntityReference, dvr.NodeType);
Assert.AreEqual(1, dvr.Depth);
dvr.ResolveEntity();
// It is still entity reference.
Assert.AreEqual(XmlNodeType.EntityReference, dvr.NodeType);
dvr.Read();
Assert.AreEqual(XmlNodeType.Text, dvr.NodeType);
Assert.AreEqual(2, dvr.Depth);
Assert.AreEqual("entity string", dvr.Value);
dvr.Read();
Assert.AreEqual(XmlNodeType.EndEntity, dvr.NodeType);
Assert.AreEqual(1, dvr.Depth);
Assert.AreEqual(String.Empty, dvr.Value);
dvr.Read(); // &ent2;
Assert.AreEqual(XmlNodeType.EntityReference, dvr.NodeType);
Assert.AreEqual(1, dvr.Depth);
dvr.ResolveEntity();
// It is still entity reference.
Assert.AreEqual(XmlNodeType.EntityReference, dvr.NodeType);
// It now became element node.
dvr.Read();
Assert.AreEqual(XmlNodeType.Element, dvr.NodeType);
Assert.AreEqual(2, dvr.Depth);
}
public static void Main()
{
XmlValidatingReader reader = null;
XmlTextReader txtreader = null;
try
{
//Create and load the XmlTextReader with the XML file.
txtreader = new XmlTextReader("book1.xml");
txtreader.WhitespaceHandling = WhitespaceHandling.None;
//Create the XmlValidatingReader over the XmlTextReader.
//Set the reader to not expand general entities.
reader = new XmlValidatingReader(txtreader);
reader.ValidationType = ValidationType.None;
reader.EntityHandling = EntityHandling.ExpandCharEntities;
reader.MoveToContent(); //Move to the root element.
reader.Read(); //Move to title start tag.
reader.Skip(); //Skip the title element.
//Read the misc start tag. The reader is now positioned on
//the entity reference node.
reader.ReadStartElement();
//Because EntityHandling is set to ExpandCharEntities, you must call
//ResolveEntity to expand the entity. The entity replacement text is
//then parsed and returned as a child node.
Console.WriteLine("Expand the entity...");
reader.ResolveEntity();
Console.WriteLine("The entity replacement text is returned as a text node.");
reader.Read();
Console.WriteLine("NodeType: {0} Value: {1}", reader.NodeType, reader.Value);
Console.WriteLine("An EndEntity node closes the entity reference scope.");
reader.Read();
Console.WriteLine("NodeType: {0} Name: {1}", reader.NodeType, reader.Name);
}
finally
{
if (reader != null)
{
reader.Close();
}
}
}
