AsymmetricAlgorithm::FromXmlString Method (String^)

 

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

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

public:
virtual void FromXmlString(
	String^ xmlString
)

Parameters

xmlString
Type: System::String^

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:
    virtual void FromXmlString(String^ xmlString) override 
    {
        if (xmlString != nullptr)
        {
            XmlDocument^ document = gcnew XmlDocument();
            document->LoadXml(xmlString);
            XmlNode^ firstNode = document->FirstChild;
            XmlNodeList^ nodeList;

            // Assemble parameters from values in each XML element.
            cryptoServiceParameters = gcnew CspParameters();

            // KeyContainerName is optional.
            nodeList = 
                document->GetElementsByTagName("KeyContainerName");
            if (nodeList->Count > 0)
            {
                cryptoServiceParameters->KeyContainerName =
                    nodeList->Item(0)->InnerText;
            }

            // KeyNumber is optional.
            nodeList = document->GetElementsByTagName("KeyNumber");
            if (nodeList->Count > 0)
            {
                cryptoServiceParameters->KeyNumber =
                    Int32::Parse(nodeList->Item(0)->InnerText);
            }

            // ProviderName is optional.
            nodeList = document->GetElementsByTagName("ProviderName");
            if (nodeList->Count > 0)
            {
                cryptoServiceParameters->ProviderName =
                    nodeList->Item(0)->InnerText;
            }

            // ProviderType is optional.
            nodeList = document->GetElementsByTagName("ProviderType");
            if (nodeList->Count > 0)
            {
                cryptoServiceParameters->ProviderType =
                    Int32::Parse(nodeList->Item(0)->InnerText);
            }
        }
        else
        {
            throw gcnew ArgumentNullException("xmlString");
        }
    }

.NET Framework
Available since 1.1
Windows Phone Silverlight
Available since 7.1
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