DtdProcessing Enumeration

Specifies the options for processing DTDs. The DtdProcessing enumeration is used by XmlReaderSettings.

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

public enum DtdProcessing

Member nameDescription
Supported by Silverlight for Windows PhoneSupported by Xbox 360ProhibitSpecifies that when a DTD is encountered, an XmlException is thrown with a message that states that DTDs are prohibited. This is the default behavior.
Supported by Silverlight for Windows PhoneSupported by Xbox 360IgnoreCauses the DOCTYPE element to be ignored. No DTD processing occurs. Warning: The DTD/DOCTYPE will be lost on output.
Supported by Silverlight for Windows PhoneSupported by Xbox 360ParseIs used for parsing DTDs.

This enumeration is set on the DtdProcessing property. In .NET Framework for Silverlight, the DtdProcessing property replaces the ProhibitDTD property in .NET Framework and adds the ability to ignore the DOCTYPE element.

The following example preloads the DTDs and entities defined in XHTML 1.0 by setting Xhtml10 on the XmlPreloadedResolver. In this example, the XHTMLPage.html file is a part of the application's XAP package; therefore, we have to pass a fallback resolver to the constructor of the XmlPreloadedResolver.

XmlReaderSettings settings = new XmlReaderSettings();
settings.DtdProcessing = DtdProcessing.Parse;
settings.XmlResolver =
    new XmlPreloadedResolver(new XmlXapResolver(),

using (XmlReader reader = XmlReader.Create("HTMLPage.html", settings))
XDocument document = XDocument.Load(reader);
OutputTextBlock.Text = document.ToString();


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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