Assembly: System.Xml (in system.xml.dll)
In the Microsoft .NET Framework version 2.0 release, the Create method is the preferred mechanism for obtaining XmlReader instances. The Create method uses the XmlReaderSettings class to specify which features to implement in the created XmlReader object.
For more information, see Creating XML Readers.
The following are things to consider when using the XmlReaderSettings class.
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 a null reference (Nothing in Visual Basic), 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.
Validation error messages may expose sensitive content model information. Validation error and warning messages are handled using the ValidationEventHandler delegate, or are exposed as an XmlSchemaValidationException if no event handler is provided to the XmlReaderSettings object (validation warnings do not cause an XmlSchemaValidationException to be thrown). This content model information should not be exposed in untrusted scenarios. Validation warning messages are suppressed by default and can be reported by setting the ReportValidationWarnings flag.
The SourceUri property of an XmlSchemaValidationException returns the URI path to the schema file that caused the exception. The SourceUri property should not be exposed in untrusted scenarios.
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.
XmlReaderSettings objects can contain sensitive information such as user credentials. You should be careful when caching XmlReaderSettings objects, or when passing the XmlReaderSettings object from one component to another.
DTD processing is disabled by default. If you enable DTD processing, you need to be aware of including DTDs from untrusted sources and possible denial of service attacks. Use the XmlSecureResolver to restrict the resources that the XmlReader can access.
The following example creates an XmlReader that uses an XmlUrlResolver with the necessary credentials.
// Create an XmlUrlResolver with the credentials necessary to access the Web server. XmlUrlResolver resolver = new XmlUrlResolver(); System.Net.NetworkCredential myCred; myCred = new System.Net.NetworkCredential(UserName,SecurelyStoredPassword,Domain); resolver.Credentials = myCred; XmlReaderSettings settings = new XmlReaderSettings(); settings.XmlResolver = resolver; // Create the reader. XmlReader reader = XmlReader.Create("http://serverName/data/books.xml", settings);
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.