XmlSchemaValidator.ValidateAttribute 方法

定义

验证当前元素上下文中的属性。

重载

ValidateAttribute(String, String, XmlValueGetter, XmlSchemaInfo)

验证当前元素上下文中的属性名称、命名空间 URI 和值。

ValidateAttribute(String, String, String, XmlSchemaInfo)

验证当前元素上下文中的属性名称、命名空间 URI 和值。

ValidateAttribute(String, String, XmlValueGetter, XmlSchemaInfo)

验证当前元素上下文中的属性名称、命名空间 URI 和值。

public:
 System::Object ^ ValidateAttribute(System::String ^ localName, System::String ^ namespaceUri, System::Xml::Schema::XmlValueGetter ^ attributeValue, System::Xml::Schema::XmlSchemaInfo ^ schemaInfo);
public object? ValidateAttribute (string localName, string namespaceUri, System.Xml.Schema.XmlValueGetter attributeValue, System.Xml.Schema.XmlSchemaInfo? schemaInfo);
public object ValidateAttribute (string localName, string namespaceUri, System.Xml.Schema.XmlValueGetter attributeValue, System.Xml.Schema.XmlSchemaInfo schemaInfo);
member this.ValidateAttribute : string * string * System.Xml.Schema.XmlValueGetter * System.Xml.Schema.XmlSchemaInfo -> obj
Public Function ValidateAttribute (localName As String, namespaceUri As String, attributeValue As XmlValueGetter, schemaInfo As XmlSchemaInfo) As Object

参数

localName
String

要验证的属性的本地名称。

namespaceUri
String

要验证的属性的命名空间 URI。

attributeValue
XmlValueGetter

一个 XmlValueGetterdelegate,用于将属性的值作为与该属性的 XML 架构定义语言 (XSD) 类型兼容的公共语言运行时 (CLR) 类型进行传递。

schemaInfo
XmlSchemaInfo

一个 XmlSchemaInfo 对象,其属性是在成功验证特性之后设置的。 此参数可以为 null

返回

Object

验证的属性的值。

例外

此特性在当前元素上下文中无效。

未按正确的顺序调用 ValidateAttribute 方法。 例如,调用 ValidateAttribute 之后又调用 ValidateEndOfAttributes(XmlSchemaInfo)

指定的一个或多个参数为 null

示例

以下示例根据contosoBooks.xsd架构验证contosoBooks.xml文件。 该示例使用 XmlSerializer 类反序列化 contosoBooks.xml 文件,并将节点的值传递给 XmlSchemaValidator 类的方法。

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;
    }
}
Imports System.Xml
Imports System.Xml.Schema
Imports System.Xml.Serialization
Imports System.Collections


Namespace Microsoft.Samples.Xml.Schema

    Class XmlSchemaValidatorExamples

        Shared Sub Main()

            ' The XML document to deserialize into the XmlSerializer object.
            Dim reader As XmlReader = XmlReader.Create("contosoBooks.xml")

            ' The XmlSerializer object.
            Dim serializer As XmlSerializer = New XmlSerializer(GetType(ContosoBooks))
            Dim books As ContosoBooks = CType(serializer.Deserialize(reader), ContosoBooks)

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

            ' The XmlNamespaceManager object used to handle namespaces.
            Dim manager As XmlNamespaceManager = New XmlNamespaceManager(reader.NameTable)

            ' Assign a ValidationEventHandler to handle schema validation warnings and errors.
            Dim validator As XmlSchemaValidator = New XmlSchemaValidator(reader.NameTable, schemaSet, manager, XmlSchemaValidationFlags.None)
            'validator.ValidationEventHandler += New ValidationEventHandler(SchemaValidationEventHandler)
            AddHandler validator.ValidationEventHandler, AddressOf 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", Nothing)

            validator.GetUnspecifiedDefaultAttributes(New ArrayList())
            validator.ValidateEndOfAttributes(Nothing)

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

            For Each book As BookType In books.book
                ' Validate the book element.
                validator.ValidateElement("book", "http://www.contoso.com/books", Nothing)

                ' Get the exptected attributes for the book element.
                Console.Write(vbCrLf & "Expected attributes: ")
                Dim attributes() As XmlSchemaAttribute = validator.GetExpectedAttributes()
                For Each attribute As XmlSchemaAttribute In attributes
                    Console.Write("'{0}' ", attribute.Name)
                Next
                Console.WriteLine()

                ' Validate the genre attribute and display its post schema validation information.
                If Not book.Genre Is Nothing Then
                    validator.ValidateAttribute("genre", "", book.Genre, schemaInfo)
                End If
                DisplaySchemaInfo()

                ' Validate the publicationdate attribute and display its post schema validation information.
                If Not book.PublicationDate = Nothing Then
                    validator.ValidateAttribute("publicationdate", "", dateTimeGetter(book.PublicationDate), schemaInfo)
                End If
                DisplaySchemaInfo()

                ' Validate the ISBN attribute and display its post schema validation information.
                If Not book.Isbn Is Nothing Then
                    validator.ValidateAttribute("ISBN", "", book.Isbn, schemaInfo)
                End If
                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(Nothing)

                ' Validate the title element and its content.
                validator.ValidateElement("title", "http://www.contoso.com/books", Nothing)
                validator.ValidateEndElement(Nothing, 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", Nothing)

                validator.GetUnspecifiedDefaultAttributes(New ArrayList())
                validator.ValidateEndOfAttributes(Nothing)

                If Not book.Author.Name Is Nothing Then
                    ' Validate the name element and its content.
                    validator.ValidateElement("name", "http://www.contoso.com/books", Nothing)
                    validator.ValidateEndElement(Nothing, book.Author.Name)
                End If

                If Not book.Author.FirstName Is Nothing Then
                    ' Validate the first-name element and its content.
                    validator.ValidateElement("first-name", "http://www.contoso.com/books", Nothing)
                    validator.ValidateEndElement(Nothing, book.Author.FirstName)

                End If

                If Not book.Author.LastName Is Nothing Then
                    ' Validate the last-name element and its content.
                    validator.ValidateElement("last-name", "http://www.contoso.com/books", Nothing)
                    validator.ValidateEndElement(Nothing, book.Author.LastName)
                End If

                ' Validate the content of the author element.
                validator.ValidateEndElement(Nothing)

                ' Validate the price element and its content.
                validator.ValidateElement("price", "http://www.contoso.com/books", Nothing)
                validator.ValidateEndElement(Nothing, book.Price)

                ' Validate the content of the book element.
                validator.ValidateEndElement(Nothing)
            Next

            ' Validate the content of the bookstore element.
            validator.ValidateEndElement(Nothing)

            ' Close the XmlReader object.
            reader.Close()

        End Sub

        Shared schemaInfo As XmlSchemaInfo = New XmlSchemaInfo()
        Shared dateTimeGetterContent As Object

        Shared Function dateTimeGetterHandle() As Object

            Return dateTimeGetterContent

        End Function

        Shared Function dateTimeGetter(ByVal dateTime As DateTime) As XmlValueGetter

            dateTimeGetterContent = dateTime
            Return New XmlValueGetter(AddressOf dateTimeGetterHandle)

        End Function

        Shared Sub DisplaySchemaInfo()

            If Not schemaInfo.SchemaElement Is Nothing Then
                Console.WriteLine("Element '{0}' with type '{1}' is '{2}'", schemaInfo.SchemaElement.Name, schemaInfo.SchemaType, schemaInfo.Validity)
            ElseIf Not schemaInfo.SchemaAttribute Is Nothing Then
                Console.WriteLine("Attribute '{0}' with type '{1}' is '{2}'", schemaInfo.SchemaAttribute.Name, schemaInfo.SchemaType, schemaInfo.Validity)
            End If

        End Sub

        Shared Sub SchemaValidationEventHandler(ByVal sender As Object, ByVal e As ValidationEventArgs)

            Select Case e.Severity
                Case XmlSeverityType.Error
                    Console.WriteLine(vbCrLf & "Error: {0}", e.Message)
                    Exit Sub
                Case XmlSeverityType.Warning
                    Console.WriteLine(vbCrLf & "Warning: {0}", e.Message)
                    Exit Sub
            End Select

        End Sub

    End Class

    <XmlRootAttribute("bookstore", Namespace:="http://www.contoso.com/books", IsNullable:=False)> _
    Public Class ContosoBooks

        <XmlElementAttribute("book")> _
        Public book() As BookType

    End Class

    Public Class BookType

        <XmlAttributeAttribute("genre")> _
        Public Genre As String

        <XmlAttributeAttribute("publicationdate", DataType:="date")> _
        Public PublicationDate As DateTime

        <XmlAttributeAttribute("ISBN")> _
        Public Isbn As String

        <XmlElementAttribute("title")> _
        Public Title As String

        <XmlElementAttribute("author")> _
        Public Author As BookAuthor

        <XmlElementAttribute("price")> _
        Public Price As Decimal

    End Class

    Public Class BookAuthor

        <XmlElementAttribute("name")> _
        Public Name As String

        <XmlElementAttribute("first-name")> _
        Public FirstName As String

        <XmlElementAttribute("last-name")> _
        Public LastName As String

    End Class

End Namespace

该示例使用 contosoBooks.xml 文件作为输入。

<?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>

该示例还使用 contosoBooks.xsd 作为输入。

<?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>

注解

以下是使用 ValidateAttribute 该方法时要考虑的重要说明。

另请参阅

适用于

ValidateAttribute(String, String, String, XmlSchemaInfo)

验证当前元素上下文中的属性名称、命名空间 URI 和值。

public:
 System::Object ^ ValidateAttribute(System::String ^ localName, System::String ^ namespaceUri, System::String ^ attributeValue, System::Xml::Schema::XmlSchemaInfo ^ schemaInfo);
public object? ValidateAttribute (string localName, string namespaceUri, string attributeValue, System.Xml.Schema.XmlSchemaInfo? schemaInfo);
public object ValidateAttribute (string localName, string namespaceUri, string attributeValue, System.Xml.Schema.XmlSchemaInfo schemaInfo);
member this.ValidateAttribute : string * string * string * System.Xml.Schema.XmlSchemaInfo -> obj
Public Function ValidateAttribute (localName As String, namespaceUri As String, attributeValue As String, schemaInfo As XmlSchemaInfo) As Object

参数

localName
String

要验证的属性的本地名称。

namespaceUri
String

要验证的属性的命名空间 URI。

attributeValue
String

要验证的属性的值。

schemaInfo
XmlSchemaInfo

一个 XmlSchemaInfo 对象,其属性是在成功验证特性之后设置的。 此参数可以为 null

返回

Object

验证的属性的值。

例外

此特性在当前元素上下文中无效。

未按正确的顺序调用 ValidateAttribute 方法。 例如,调用 ValidateAttribute 之后又调用 ValidateEndOfAttributes(XmlSchemaInfo)

指定的一个或多个参数为 null

示例

以下示例根据contosoBooks.xsd架构验证contosoBooks.xml文件。 该示例使用 XmlSerializer 类反序列化 contosoBooks.xml 文件,并将节点的值传递给 XmlSchemaValidator 类的方法。

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;
    }
}
Imports System.Xml
Imports System.Xml.Schema
Imports System.Xml.Serialization
Imports System.Collections


Namespace Microsoft.Samples.Xml.Schema

    Class XmlSchemaValidatorExamples

        Shared Sub Main()

            ' The XML document to deserialize into the XmlSerializer object.
            Dim reader As XmlReader = XmlReader.Create("contosoBooks.xml")

            ' The XmlSerializer object.
            Dim serializer As XmlSerializer = New XmlSerializer(GetType(ContosoBooks))
            Dim books As ContosoBooks = CType(serializer.Deserialize(reader), ContosoBooks)

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

            ' The XmlNamespaceManager object used to handle namespaces.
            Dim manager As XmlNamespaceManager = New XmlNamespaceManager(reader.NameTable)

            ' Assign a ValidationEventHandler to handle schema validation warnings and errors.
            Dim validator As XmlSchemaValidator = New XmlSchemaValidator(reader.NameTable, schemaSet, manager, XmlSchemaValidationFlags.None)
            'validator.ValidationEventHandler += New ValidationEventHandler(SchemaValidationEventHandler)
            AddHandler validator.ValidationEventHandler, AddressOf 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", Nothing)

            validator.GetUnspecifiedDefaultAttributes(New ArrayList())
            validator.ValidateEndOfAttributes(Nothing)

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

            For Each book As BookType In books.book
                ' Validate the book element.
                validator.ValidateElement("book", "http://www.contoso.com/books", Nothing)

                ' Get the exptected attributes for the book element.
                Console.Write(vbCrLf & "Expected attributes: ")
                Dim attributes() As XmlSchemaAttribute = validator.GetExpectedAttributes()
                For Each attribute As XmlSchemaAttribute In attributes
                    Console.Write("'{0}' ", attribute.Name)
                Next
                Console.WriteLine()

                ' Validate the genre attribute and display its post schema validation information.
                If Not book.Genre Is Nothing Then
                    validator.ValidateAttribute("genre", "", book.Genre, schemaInfo)
                End If
                DisplaySchemaInfo()

                ' Validate the publicationdate attribute and display its post schema validation information.
                If Not book.PublicationDate = Nothing Then
                    validator.ValidateAttribute("publicationdate", "", dateTimeGetter(book.PublicationDate), schemaInfo)
                End If
                DisplaySchemaInfo()

                ' Validate the ISBN attribute and display its post schema validation information.
                If Not book.Isbn Is Nothing Then
                    validator.ValidateAttribute("ISBN", "", book.Isbn, schemaInfo)
                End If
                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(Nothing)

                ' Validate the title element and its content.
                validator.ValidateElement("title", "http://www.contoso.com/books", Nothing)
                validator.ValidateEndElement(Nothing, 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", Nothing)

                validator.GetUnspecifiedDefaultAttributes(New ArrayList())
                validator.ValidateEndOfAttributes(Nothing)

                If Not book.Author.Name Is Nothing Then
                    ' Validate the name element and its content.
                    validator.ValidateElement("name", "http://www.contoso.com/books", Nothing)
                    validator.ValidateEndElement(Nothing, book.Author.Name)
                End If

                If Not book.Author.FirstName Is Nothing Then
                    ' Validate the first-name element and its content.
                    validator.ValidateElement("first-name", "http://www.contoso.com/books", Nothing)
                    validator.ValidateEndElement(Nothing, book.Author.FirstName)

                End If

                If Not book.Author.LastName Is Nothing Then
                    ' Validate the last-name element and its content.
                    validator.ValidateElement("last-name", "http://www.contoso.com/books", Nothing)
                    validator.ValidateEndElement(Nothing, book.Author.LastName)
                End If

                ' Validate the content of the author element.
                validator.ValidateEndElement(Nothing)

                ' Validate the price element and its content.
                validator.ValidateElement("price", "http://www.contoso.com/books", Nothing)
                validator.ValidateEndElement(Nothing, book.Price)

                ' Validate the content of the book element.
                validator.ValidateEndElement(Nothing)
            Next

            ' Validate the content of the bookstore element.
            validator.ValidateEndElement(Nothing)

            ' Close the XmlReader object.
            reader.Close()

        End Sub

        Shared schemaInfo As XmlSchemaInfo = New XmlSchemaInfo()
        Shared dateTimeGetterContent As Object

        Shared Function dateTimeGetterHandle() As Object

            Return dateTimeGetterContent

        End Function

        Shared Function dateTimeGetter(ByVal dateTime As DateTime) As XmlValueGetter

            dateTimeGetterContent = dateTime
            Return New XmlValueGetter(AddressOf dateTimeGetterHandle)

        End Function

        Shared Sub DisplaySchemaInfo()

            If Not schemaInfo.SchemaElement Is Nothing Then
                Console.WriteLine("Element '{0}' with type '{1}' is '{2}'", schemaInfo.SchemaElement.Name, schemaInfo.SchemaType, schemaInfo.Validity)
            ElseIf Not schemaInfo.SchemaAttribute Is Nothing Then
                Console.WriteLine("Attribute '{0}' with type '{1}' is '{2}'", schemaInfo.SchemaAttribute.Name, schemaInfo.SchemaType, schemaInfo.Validity)
            End If

        End Sub

        Shared Sub SchemaValidationEventHandler(ByVal sender As Object, ByVal e As ValidationEventArgs)

            Select Case e.Severity
                Case XmlSeverityType.Error
                    Console.WriteLine(vbCrLf & "Error: {0}", e.Message)
                    Exit Sub
                Case XmlSeverityType.Warning
                    Console.WriteLine(vbCrLf & "Warning: {0}", e.Message)
                    Exit Sub
            End Select

        End Sub

    End Class

    <XmlRootAttribute("bookstore", Namespace:="http://www.contoso.com/books", IsNullable:=False)> _
    Public Class ContosoBooks

        <XmlElementAttribute("book")> _
        Public book() As BookType

    End Class

    Public Class BookType

        <XmlAttributeAttribute("genre")> _
        Public Genre As String

        <XmlAttributeAttribute("publicationdate", DataType:="date")> _
        Public PublicationDate As DateTime

        <XmlAttributeAttribute("ISBN")> _
        Public Isbn As String

        <XmlElementAttribute("title")> _
        Public Title As String

        <XmlElementAttribute("author")> _
        Public Author As BookAuthor

        <XmlElementAttribute("price")> _
        Public Price As Decimal

    End Class

    Public Class BookAuthor

        <XmlElementAttribute("name")> _
        Public Name As String

        <XmlElementAttribute("first-name")> _
        Public FirstName As String

        <XmlElementAttribute("last-name")> _
        Public LastName As String

    End Class

End Namespace

该示例使用 contosoBooks.xml 文件作为输入。

<?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>

该示例还使用 contosoBooks.xsd 作为输入。

<?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>

注解

以下是使用 ValidateAttribute 该方法时要考虑的重要说明。

另请参阅

适用于