Extensions.GetSchemaInfo Method (XElement)

 
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Gets the post-schema-validation infoset (PSVI) of a validated element.

Namespace:   System.Xml.Schema
Assembly:  System.Xml.Linq (in System.Xml.Linq.dll)

public static IXmlSchemaInfo GetSchemaInfo(
	this XElement source
)

Parameters

source
Type: System.Xml.Linq.XElement

An XElement that has been previously validated.

Return Value

Type: System.Xml.Schema.IXmlSchemaInfo

A IXmlSchemaInfo that contains the post-schema-validation infoset (PSVI) for an XElement.

You can use the IXmlSchemaInfo returned by this method to determine certain characteristics of a validated element. For example, you can determine the dynamic schema type of the element.

You use the SchemaElement property to get a partial validation type (XmlSchemaElement). You can use it to revalidate a sub-tree with an element at its root without validating an entire document.

For an example of this property, see Validate.

The following example populates the tree with a PSVI. After validation, it prints all elements and attributes in the tree that are invalid according to the PSVI.


                static void DumpInvalidNodes(XElement el)
{
    if (el.GetSchemaInfo().Validity != XmlSchemaValidity.Valid)
        Console.WriteLine("Invalid Element {0}",
            el.AncestorsAndSelf()
            .InDocumentOrder()
            .Aggregate("", (s, i) => s + "/" + i.Name.ToString()));
    foreach (XAttribute att in el.Attributes())
        if (att.GetSchemaInfo().Validity != XmlSchemaValidity.Valid)
            Console.WriteLine("Invalid Attribute {0}",
                att
                .Parent
                .AncestorsAndSelf()
                .InDocumentOrder()
                .Aggregate("",
                    (s, i) => s + "/" + i.Name.ToString()) + "/@" + att.Name.ToString()
                );
    foreach (XElement child in el.Elements())
        DumpInvalidNodes(child);
}

static void Main(string[] args)
{
    string xsdMarkup =
         @"<xsd:schema xmlns:xsd='http://www.w3.org/2001/XMLSchema'>
   <xsd:simpleType name='GCType'>
    <xsd:restriction base='xsd:token'>
     <xsd:enumeration value='AAA'/>
     <xsd:enumeration value='BBB'/>
    </xsd:restriction>
   </xsd:simpleType>
   <xsd:element name='Root'>
    <xsd:complexType>
     <xsd:sequence>
      <xsd:element name='Child1' minOccurs='1' maxOccurs='1'>
       <xsd:complexType>
        <xsd:sequence>
         <xsd:element name='GrandChild1' type='GCType'/>
         <xsd:element name='GrandChild2' type='GCType'/>
         <xsd:element name='GrandChild3' type='GCType'/>
        </xsd:sequence>
       </xsd:complexType>
      </xsd:element>
     </xsd:sequence>
    </xsd:complexType>
   </xsd:element>
  </xsd:schema>";

    XmlSchemaSet schemas = new XmlSchemaSet();
    schemas.Add("", XmlReader.Create(new StringReader(xsdMarkup)));

    XDocument doc1 = new XDocument(
        new XElement("Root",
            new XElement("Child1",
                new XElement("GrandChild1", "AAA"),
                new XElement("GrandChild2", "ZZZ"),
                new XElement("GrandChild3", "ZZZ")
            )
        )
    );

    Console.WriteLine("Validating doc1 ...");
    bool errors = false;
    doc1.Validate(schemas, (sender, e) =>
    {
        Console.WriteLine(e.Message);
        errors = true;
    }, true);
    Console.WriteLine("doc1 {0}", errors ? "did not validate" : "validated");
    DumpInvalidNodes(doc1.Root);
}

This example produces the following output:

Validating doc1 ...
The 'GrandChild2' element is invalid - The value 'ZZZ' is invalid according to its datatype 'GCType' - The Enumeration constraint failed.
The 'GrandChild3' element is invalid - The value 'ZZZ' is invalid according to its datatype 'GCType' - The Enumeration constraint failed.
doc1 did not validate
Invalid Element /Root
Invalid Element /Root/Child1
Invalid Element /Root/Child1/GrandChild2
Invalid Element /Root/Child1/GrandChild3

.NET Framework
Available since 3.5
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