FromXmlString Method

AsymmetricAlgorithm.FromXmlString Method

When overridden in a derived class, reconstructs an AsymmetricAlgorithm object from an XML string.

Namespace: System.Security.Cryptography
Assembly: mscorlib (in mscorlib.dll)

Public MustOverride Sub FromXmlString ( _
	xmlString As String _
Dim instance As AsymmetricAlgorithm
Dim xmlString As String

public abstract void FromXmlString (
	String xmlString
public abstract function FromXmlString (
	xmlString : String
Not applicable.



The XML string to use to reconstruct the AsymmetricAlgorithm object.

The following code example demonstrates how to implement the FromXmlString method to parse the specified XML string to populate the current CspParameters object. This code example is part of a larger example provided for the AsymmetricAlgorithm class.

' Expected XML schema:
'  <CustomCryptoKeyValue>
'      <ProviderName></ProviderName>
'      <KeyContainerName></KeyContainerName>
'      <KeyNumber></KeyNumber>
'      <ProviderType></ProviderType>
'  </CustomCryptoKeyValue>
Public Overrides Sub FromXmlString(ByVal xmlString As String)
    If Not xmlString Is Nothing Then
        Dim doc As New XmlDocument
        Dim firstNode As XmlNode = doc.FirstChild
        Dim nodeList As XmlNodeList

        ' Assemble parameters from values in each XML element.
        cspParameters = New CspParameters

        ' KeyContainerName is optional.
        nodeList = doc.GetElementsByTagName("KeyContainerName")
        Dim keyName As String = nodeList.Item(0).InnerText
        If Not keyName Is Nothing Then
            cspParameters.KeyContainerName = keyName
        End If

        ' KeyNumber is optional.
        nodeList = doc.GetElementsByTagName("KeyNumber")
        Dim keyNumber As String = nodeList.Item(0).InnerText
        If Not keyNumber Is Nothing Then
            cspParameters.KeyNumber = Int32.Parse(keyNumber)
        End If

        ' ProviderName is optional.
        nodeList = doc.GetElementsByTagName("ProviderName")
        Dim providerName As String = nodeList.Item(0).InnerText
        If Not providerName Is Nothing Then
            cspParameters.ProviderName = providerName
        End If

        ' ProviderType is optional.
        nodeList = doc.GetElementsByTagName("ProviderType")
        Dim providerType As String = nodeList.Item(0).InnerText
        If Not providerType Is Nothing Then
            cspParameters.ProviderType = Int32.Parse(providerType)
        End If
        Throw New ArgumentNullException("xmlString")
    End If
End Sub

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

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