XmlReaderSettings.ProhibitDtd Property

 
System_CAPS_noteNote

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Note: This API is now obsolete.

Gets or sets a value indicating whether to prohibit document type definition (DTD) processing. This property is obsolete. Use DtdProcessing instead.

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

<ObsoleteAttribute("Use XmlReaderSettings.DtdProcessing property instead.")>
Public Property ProhibitDtd As Boolean

Property Value

Type: System.Boolean

true to prohibit DTD processing; otherwise false. The default is true.

When set to true, the XmlReader throws an XmlException when any DTD content is encountered. Do not enable DTD processing if you are concerned about Denial of Service issues or if you are dealing with untrusted sources.

If you have DTD processing enabled, you can use the XmlSecureResolver to restrict the resources that the XmlReader can access. You can also design your application so that the XML processing is memory and time constrained. For example, configure time-out limits in your ASP.NET application.

This property is obsolete. Use DtdProcessing instead. If you had set ProhibitDtd to its default value true set DtdProcessing to Prohibit. If you had set ProhibitDtd to false set DtdProcessing to Parse.

The following example validates data using a DTD.

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

public class Sample 

  public shared sub Main() 

    ' Set the validation settings.
    Dim settings as XmlReaderSettings = new XmlReaderSettings()
    settings.DtdProcessing = DtdProcessing.Parse
    settings.ValidationType = ValidationType.DTD
    AddHandler settings.ValidationEventHandler, AddressOf ValidationCallBack

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

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

  end sub

  ' Display any validation errors.
  private shared sub ValidationCallBack(sender as object, e as ValidationEventArgs) 
    Console.WriteLine("Validation Error: {0}", e.Message)
  end sub
end class

The example uses the itemDTD.xml file as input.

<!--XML file using a DTD-->
<!DOCTYPE store [
  <!ELEMENT store (item)*> 
  <!ELEMENT item (name,dept,price)>
  <!ATTLIST item type CDATA #REQUIRED>
  <!ELEMENT name (#PCDATA)>
  <!ELEMENT price (#PCDATA)>]>
<store>
  <item type="supplies"  ISBN="2-3631-4">
    <name>paint</name>
    <price>16.95</price>
  </item>
</store>

.NET Framework
Available since 2.0
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