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XmlReaderSettings.ValidationFlags Property

  • Reference

Definition

Namespace:
System.Xml
Assembly:
System.Xml.ReaderWriter.dll
Assembly:
System.Xml.dll
Assembly:
netstandard.dll
Source:
XmlReaderSettings.cs
Source:
XmlReaderSettings.cs
Source:
XmlReaderSettings.cs

Gets or sets a value indicating the schema validation settings. This setting applies to XmlReader objects that validate schemas (ValidationType property set to ValidationType.Schema).

public:
 property System::Xml::Schema::XmlSchemaValidationFlags ValidationFlags { System::Xml::Schema::XmlSchemaValidationFlags get(); void set(System::Xml::Schema::XmlSchemaValidationFlags value); };
public System.Xml.Schema.XmlSchemaValidationFlags ValidationFlags { get; set; }
member this.ValidationFlags : System.Xml.Schema.XmlSchemaValidationFlags with get, set
Public Property ValidationFlags As XmlSchemaValidationFlags

Property Value

XmlSchemaValidationFlags

A bitwise combination of enumeration values that specify validation options. ProcessIdentityConstraints and AllowXmlAttributes are enabled by default. ProcessInlineSchema, ProcessSchemaLocation, and ReportValidationWarnings are disabled by default.

Examples

The following example validates an XML file against an inline XML Schema by enabling the ProcessInlineSchema setting. The XML reader is configured to display validation warnings, so you also see the expected warning on the root element.

using System;
using System.Xml;
using System.Xml.Schema;
using System.IO;

public class ValidXSD {

  public static void Main() {

    // Set the validation settings.
    XmlReaderSettings settings = new XmlReaderSettings();
    settings.ValidationType = ValidationType.Schema;
    settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessInlineSchema;
    settings.ValidationFlags |= XmlSchemaValidationFlags.ReportValidationWarnings;
    settings.ValidationEventHandler += new ValidationEventHandler (ValidationCallBack);

    // Create the XmlReader object.
    XmlReader reader = XmlReader.Create("inlineSchema.xml", settings);

    // Parse the file.
    while (reader.Read());
  }

  // Display any warnings or errors.
  private static void ValidationCallBack (object sender, ValidationEventArgs args) {
     if (args.Severity==XmlSeverityType.Warning)
       Console.WriteLine("\tWarning: Matching schema not found.  No validation occurred." + args.Message);
     else
        Console.WriteLine("\tValidation error: " + args.Message);
  }
}

Imports System.Xml
Imports System.Xml.Schema
Imports System.IO

public class ValidXSD 

  public shared sub Main() 

    ' Set the validation settings.
    Dim settings as XmlReaderSettings = new XmlReaderSettings()
    settings.ValidationType = ValidationType.Schema
    settings.ValidationFlags = settings.ValidationFlags Or XmlSchemaValidationFlags.ProcessInlineSchema
    settings.ValidationFlags = settings.ValidationFlags Or XmlSchemaValidationFlags.ReportValidationWarnings
      AddHandler settings.ValidationEventHandler, AddressOf ValidationCallBack

    ' Create the XmlReader object.
    Dim reader as XmlReader = XmlReader.Create("inlineSchema.xml", settings)

    ' Parse the file. 
    while (reader.Read())
    end while
  end sub

  ' Display any warnings or errors.
  private shared sub ValidationCallBack (sender as object, args as ValidationEventArgs)
     if (args.Severity=XmlSeverityType.Warning)
       Console.WriteLine("   Warning: Matching schema not found.  No validation occurred." + args.Message)
     else
        Console.WriteLine("   Validation error: " + args.Message)
     end if
  end sub 

end class

The example uses the inlineSchema.xml file as input.

<root>
<!--Start of schema-->
<xs:schema xmlns:xs='http://www.w3.org/2001/XMLSchema'
            xmlns='xsdHeadCount'
            targetNamespace='xsdHeadCount'>
    <xs:element name='HeadCount'>
        <xs:complexType>
            <xs:sequence>
                <xs:element name='ID' type='xs:unsignedShort' maxOccurs='unbounded' />
            </xs:sequence>
            <xs:attribute name='division' type='xs:string' use='optional' default='QA'/>
        </xs:complexType>
    </xs:element>
</xs:schema>
<!--End of schema-->
<hc:HeadCount xmlns:hc='xsdHeadCount'>
    <ID>12365</ID>
    <ID>43295</ID>
    <division>Accounting</division>
</hc:HeadCount>
</root>

The output is as follows:

Warning: Matching schema not found. No validation occurred. Could not find schema information for the element 'root'.

Validation error: The element 'xsdHeadCount:HeadCount' has invalid child element 'division'. Expected 'ID'.

Remarks

Important

The ProcessInlineSchema and ProcessSchemaLocation validation flags of an XmlReaderSettings object are not set by default. When these flags are set, the XmlResolver of the XmlReaderSettings object is used to resolve schema locations encountered in the instance document in the XmlReader. If the XmlResolver object is null, schema locations are not resolved even if the ProcessInlineSchema and ProcessSchemaLocation validation flags are set.

Schemas added during validation add new types and can change the validation outcome of the document being validated. As a result, external schemas should only be resolved from trusted sources.

Disabling the ProcessIdentityConstraints flag (enabled by default) is recommended when validating, untrusted, large XML documents in high availability scenarios against a schema with identity constraints over a large part of the document.

Applies to

See also