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XmlSchemaValidator Class

Represents an XML Schema Definition Language (XSD) Schema validation engine. The XmlSchemaValidator class cannot be inherited.

System.Object
  System.Xml.Schema.XmlSchemaValidator

Namespace:  System.Xml.Schema
Assembly:  System.Xml (in System.Xml.dll)
public sealed class XmlSchemaValidator

The XmlSchemaValidator type exposes the following members.

  Name Description
Public method Supported by the XNA Framework XmlSchemaValidator Initializes a new instance of the XmlSchemaValidator class.
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  Name Description
Public property Supported by the XNA Framework LineInfoProvider Gets or sets the line number information for the XML node being validated.
Public property Supported by the XNA Framework SourceUri Gets or sets the source URI for the XML node being validated.
Public property Supported by the XNA Framework ValidationEventSender Gets or sets the object sent as the sender object of a validation event.
Public property Supported by the XNA Framework XmlResolver Sets the XmlResolver object used to resolve xs:import and xs:include elements as well as xsi:schemaLocation and xsi:noNamespaceSchemaLocation attributes.
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  Name Description
Public method Supported by the XNA Framework AddSchema Adds an XML Schema Definition Language (XSD) schema to the set of schemas used for validation.
Public method Supported by the XNA Framework EndValidation Ends validation and checks identity constraints for the entire XML document.
Public method Supported by the XNA Framework Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected method Supported by the XNA Framework Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method Supported by the XNA Framework GetExpectedAttributes Returns the expected attributes for the current element context.
Public method Supported by the XNA Framework GetExpectedParticles Returns the expected particles in the current element context.
Public method Supported by the XNA Framework GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method Supported by the XNA Framework GetType Gets the Type of the current instance. (Inherited from Object.)
Public method Supported by the XNA Framework GetUnspecifiedDefaultAttributes Validates identity constraints on the default attributes and populates the ArrayList specified with XmlSchemaAttribute objects for any attributes with default values that have not been previously validated using the ValidateAttribute method in the element context.
Public method Supported by the XNA Framework Initialize Initializes the state of the XmlSchemaValidator object.
Public method Supported by the XNA Framework Initialize(XmlSchemaObject) Initializes the state of the XmlSchemaValidator object using the XmlSchemaObject specified for partial validation.
Protected method Supported by the XNA Framework MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method Supported by the XNA Framework SkipToEndElement Skips validation of the current element content and prepares the XmlSchemaValidator object to validate content in the parent element's context.
Public method Supported by the XNA Framework ToString Returns a string that represents the current object. (Inherited from Object.)
Public method Supported by the XNA Framework ValidateAttribute(String, String, String, XmlSchemaInfo) Validates the attribute name, namespace URI, and value in the current element context.
Public method Supported by the XNA Framework ValidateAttribute(String, String, XmlValueGetter, XmlSchemaInfo) Validates the attribute name, namespace URI, and value in the current element context.
Public method Supported by the XNA Framework ValidateElement(String, String, XmlSchemaInfo) Validates the element in the current context.
Public method Supported by the XNA Framework ValidateElement(String, String, XmlSchemaInfo, String, String, String, String) Validates the element in the current context with the xsi:Type, xsi:Nil, xsi:SchemaLocation, and xsi:NoNamespaceSchemaLocation attribute values specified.
Public method Supported by the XNA Framework ValidateEndElement(XmlSchemaInfo) Verifies if the text content of the element is valid according to its data type for elements with simple content, and verifies if the content of the current element is complete for elements with complex content.
Public method Supported by the XNA Framework ValidateEndElement(XmlSchemaInfo, Object) Verifies if the text content of the element specified is valid according to its data type.
Public method Supported by the XNA Framework ValidateEndOfAttributes Verifies whether all the required attributes in the element context are present and prepares the XmlSchemaValidator object to validate the child content of the element.
Public method Supported by the XNA Framework ValidateText(String) Validates whether the text string specified is allowed in the current element context, and accumulates the text for validation if the current element has simple content.
Public method Supported by the XNA Framework ValidateText(XmlValueGetter) Validates whether the text returned by the XmlValueGetter object specified is allowed in the current element context, and accumulates the text for validation if the current element has simple content.
Public method Supported by the XNA Framework ValidateWhitespace(String) Validates whether the white space in the string specified is allowed in the current element context, and accumulates the white space for validation if the current element has simple content.
Public method Supported by the XNA Framework ValidateWhitespace(XmlValueGetter) Validates whether the white space returned by the XmlValueGetter object specified is allowed in the current element context, and accumulates the white space for validation if the current element has simple content.
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  Name Description
Public event Supported by the XNA Framework ValidationEventHandler The ValidationEventHandler that receives schema validation warnings and errors encountered during schema validation.
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The XmlSchemaValidator class provides an efficient, high-performance mechanism to validate XML data against XML schemas in a push-based manner. For example, the XmlSchemaValidator class allows you to validate an XML infoset in-place without having to serialize it as an XML document and then reparse the document using a validating XML reader. The XmlSchemaValidator class can also be used to build validation engines over custom XML data sources or as a way to build a validating XML writer.

For more information about the XmlSchemaValidator class, see the XmlSchemaValidator Push-Based Validation topic.

Security note Security Note

The ProcessInlineSchema and ProcessSchemaLocation validation flags of an XmlSchemaValidator object are not set be default. Additionally, the XmlResolver property of an XmlSchemaValidator object is Nothing by default. As a result, external schemas referenced in include, imports, or redefine elements are not resolved by default.

The following example validates the contosoBooks.xml file against the contosoBooks.xsd schema. The example uses the XmlSerializer class to deserialize the contosoBooks.xml file and pass the value of the nodes to the methods of the XmlSchemaValidator class.


using System;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
using System.Collections;

namespace Microsoft.Samples.Xml.Schema
{
    class XmlSchemaValidatorExamples
    {
        static void Main()
        {
            // The XML document to deserialize into the XmlSerializer object.
            XmlReader reader = XmlReader.Create("contosoBooks.xml");

            // The XmlSerializer object.
            XmlSerializer serializer = new XmlSerializer(typeof(ContosoBooks));
            ContosoBooks books = (ContosoBooks)serializer.Deserialize(reader);

            // The XmlSchemaSet object containing the schema used to validate the XML document.
            XmlSchemaSet schemaSet = new XmlSchemaSet();
            schemaSet.Add("http://www.contoso.com/books", "contosoBooks.xsd");

            // The XmlNamespaceManager object used to handle namespaces.
            XmlNamespaceManager manager = new XmlNamespaceManager(reader.NameTable);

            // Assign a ValidationEventHandler to handle schema validation warnings and errors.
            XmlSchemaValidator validator = new XmlSchemaValidator(reader.NameTable, schemaSet, manager, XmlSchemaValidationFlags.None);
            validator.ValidationEventHandler += new ValidationEventHandler(SchemaValidationEventHandler);

            // Initialize the XmlSchemaValidator object.
            validator.Initialize();

            // Validate the bookstore element, verify that all required attributes are present
            // and prepare to validate child content.
            validator.ValidateElement("bookstore", "http://www.contoso.com/books", null);
            validator.GetUnspecifiedDefaultAttributes(new ArrayList());
            validator.ValidateEndOfAttributes(null);

            // Get the next exptected element in the bookstore context.
            XmlSchemaParticle[] particles = validator.GetExpectedParticles();
            XmlSchemaElement nextElement = particles[0] as XmlSchemaElement;
            Console.WriteLine("Expected Element: '{0}'", nextElement.Name);

            foreach (BookType book in books.Book)
            {
                // Validate the book element.
                validator.ValidateElement("book", "http://www.contoso.com/books", null);

                // Get the exptected attributes for the book element.
                Console.Write("\nExpected attributes: ");
                XmlSchemaAttribute[] attributes = validator.GetExpectedAttributes();
                foreach (XmlSchemaAttribute attribute in attributes)
                {
                    Console.Write("'{0}' ", attribute.Name);
                }
                Console.WriteLine();

                // Validate the genre attribute and display its post schema validation information.
                if (book.Genre != null)
                {
                    validator.ValidateAttribute("genre", "", book.Genre, schemaInfo);
                }
                DisplaySchemaInfo();

                // Validate the publicationdate attribute and display its post schema validation information.
                if (book.PublicationDate != null)
                {
                    validator.ValidateAttribute("publicationdate", "", dateTimeGetter(book.PublicationDate), schemaInfo);
                }
                DisplaySchemaInfo();

                // Validate the ISBN attribute and display its post schema validation information.
                if (book.Isbn != null)
                {
                    validator.ValidateAttribute("ISBN", "", book.Isbn, schemaInfo);
                }
                DisplaySchemaInfo();

                // After validating all the attributes for the current element with ValidateAttribute method,
                // you must call GetUnspecifiedDefaultAttributes to validate the default attributes.
                validator.GetUnspecifiedDefaultAttributes(new ArrayList());

                // Verify that all required attributes of the book element are present
                // and prepare to validate child content.
                validator.ValidateEndOfAttributes(null);

                // Validate the title element and its content.
                validator.ValidateElement("title", "http://www.contoso.com/books", null);
                validator.ValidateEndElement(null, book.Title);

                // Validate the author element, verify that all required attributes are present
                // and prepare to validate child content.
                validator.ValidateElement("author", "http://www.contoso.com/books", null);
                validator.GetUnspecifiedDefaultAttributes(new ArrayList());
                validator.ValidateEndOfAttributes(null);

                if (book.Author.Name != null)
                {
                    // Validate the name element and its content.
                    validator.ValidateElement("name", "http://www.contoso.com/books", null);
                    validator.ValidateEndElement(null, book.Author.Name);
                }

                if (book.Author.FirstName != null)
                {
                    // Validate the first-name element and its content.
                    validator.ValidateElement("first-name", "http://www.contoso.com/books", null);
                    validator.ValidateEndElement(null, book.Author.FirstName);

                }

                if (book.Author.LastName != null)
                {
                    // Validate the last-name element and its content.
                    validator.ValidateElement("last-name", "http://www.contoso.com/books", null);
                    validator.ValidateEndElement(null, book.Author.LastName);
                }

                // Validate the content of the author element.
                validator.ValidateEndElement(null);

                // Validate the price element and its content.
                validator.ValidateElement("price", "http://www.contoso.com/books", null);
                validator.ValidateEndElement(null, book.Price);

                // Validate the content of the book element.
                validator.ValidateEndElement(null);
            }

            // Validate the content of the bookstore element.
            validator.ValidateEndElement(null);

            // Close the XmlReader object.
            reader.Close();
        }

        static XmlSchemaInfo schemaInfo = new XmlSchemaInfo();
        static object dateTimeGetterContent;

        static object dateTimeGetterHandle()
        {
            return dateTimeGetterContent;
        }

        static XmlValueGetter dateTimeGetter(DateTime dateTime)
        {
            dateTimeGetterContent = dateTime;
            return new XmlValueGetter(dateTimeGetterHandle);
        }

        static void DisplaySchemaInfo()
        {
            if (schemaInfo.SchemaElement != null)
            {
                Console.WriteLine("Element '{0}' with type '{1}' is '{2}'",
                    schemaInfo.SchemaElement.Name, schemaInfo.SchemaType, schemaInfo.Validity);
            }
            else if (schemaInfo.SchemaAttribute != null)
            {
                Console.WriteLine("Attribute '{0}' with type '{1}' is '{2}'",
                    schemaInfo.SchemaAttribute.Name, schemaInfo.SchemaType, schemaInfo.Validity);
            }
        }

        static void SchemaValidationEventHandler(object sender, ValidationEventArgs e)
        {
            switch (e.Severity)
            {
                case XmlSeverityType.Error:
                    Console.WriteLine("\nError: {0}", e.Message);
                    break;
                case XmlSeverityType.Warning:
                    Console.WriteLine("\nWarning: {0}", e.Message);
                    break;
            }
        }
    }

    [XmlRootAttribute("bookstore", Namespace = "http://www.contoso.com/books", IsNullable = false)]
    public class ContosoBooks
    {
        [XmlElementAttribute("book")]
        public BookType[] Book;
    }

    public class BookType
    {
        [XmlAttributeAttribute("genre")]
        public string Genre;

        [XmlAttributeAttribute("publicationdate", DataType = "date")]
        public DateTime PublicationDate;

        [XmlAttributeAttribute("ISBN")]
        public string Isbn;

        [XmlElementAttribute("title")]
        public string Title;

        [XmlElementAttribute("author")]
        public BookAuthor Author;

        [XmlElementAttribute("price")]
        public Decimal Price;
    }

    public class BookAuthor
    {
        [XmlElementAttribute("name")]
        public string Name;

        [XmlElementAttribute("first-name")]
        public string FirstName;

        [XmlElementAttribute("last-name")]
        public string LastName;
    }
}


The example takes the contosoBooks.xml file as input.


<?xml version="1.0" encoding="utf-8" ?>
<bookstore xmlns="http://www.contoso.com/books">
    <book genre="autobiography" publicationdate="1981-03-22" ISBN="1-861003-11-0">
        <title>The Autobiography of Benjamin Franklin</title>
        <author>
            <first-name>Benjamin</first-name>
            <last-name>Franklin</last-name>
        </author>
        <price>8.99</price>
    </book>
    <book genre="novel" publicationdate="1967-11-17" ISBN="0-201-63361-2">
        <title>The Confidence Man</title>
        <author>
            <first-name>Herman</first-name>
            <last-name>Melville</last-name>
        </author>
        <price>11.99</price>
    </book>
    <book genre="philosophy" publicationdate="1991-02-15" ISBN="1-861001-57-6">
        <title>The Gorgias</title>
        <author>
            <name>Plato</name>
        </author>
        <price>9.99</price>
    </book>
</bookstore>


The example also takes the contosoBooks.xsd as an input.


<?xml version="1.0" encoding="utf-8"?>
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.contoso.com/books" xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:element name="bookstore">
        <xs:complexType>
            <xs:sequence>
                <xs:element maxOccurs="unbounded" name="book">
                    <xs:complexType>
                        <xs:sequence>
                            <xs:element name="title" type="xs:string" />
                            <xs:element name="author">
                                <xs:complexType>
                                    <xs:sequence>
                                        <xs:element minOccurs="0" name="name" type="xs:string" />
                                        <xs:element minOccurs="0" name="first-name" type="xs:string" />
                                        <xs:element minOccurs="0" name="last-name" type="xs:string" />
                                    </xs:sequence>
                                </xs:complexType>
                            </xs:element>
                            <xs:element name="price" type="xs:decimal" />
                        </xs:sequence>
                        <xs:attribute name="genre" type="xs:string" use="required" />
                        <xs:attribute name="publicationdate" type="xs:date" use="required" />
                        <xs:attribute name="ISBN" type="xs:string" use="required" />
                    </xs:complexType>
                </xs:element>
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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