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XmlReaderSettings.MaxCharactersInDocument Property

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets or sets a value indicating the maximum allowable number of characters XML document. A zero (0) value means no limits on the size of the XML document. A non-zero value specifies the maximum size, in characters.

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

Syntax

'Declaration
Public Property MaxCharactersInDocument As Long
public long MaxCharactersInDocument { get; set; }

Property Value

Type: System.Int64
The maximum allowable number of characters in an XML document. The default is 0.

Remarks

A zero (0) value means no limits on the number of characters in the parsed document. A non-zero value specifies the maximum number of characters that can be parsed.

The maximum character count for the document includes the count of characters that result from expanded entities.

If the reader attempts to read a document with a size that exceeds this property, an XmlException will be thrown.

This property allows you to mitigate denial of service attacks where the attacker submits extremely large XML documents. By limiting the size of a document, you can detect the attack and recover reliably.

Examples

Dim markup As String = "<Root>Content</Root>"


Dim settings As New XmlReaderSettings()
settings.MaxCharactersInDocument = 10

Try
    Using reader As XmlReader = XmlReader.Create(New StringReader(markup), settings)
        While reader.Read()
        End While
    End Using
Catch ex As XmlException
    OutputTextBlock.Text = ex.Message
End Try
                string markup = "<Root>Content</Root>";


                XmlReaderSettings settings = new XmlReaderSettings();
                settings.MaxCharactersInDocument = 10;

                try
                {
                    using (XmlReader reader = XmlReader.Create(new StringReader(markup), settings))
                    {
                       while (reader.Read()) { }
                    }
                }
                catch (XmlException ex)
                {
                    OutputTextBlock.Text = ex.Message;
                }

Version Information

Silverlight

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

Platforms

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