How to solve “unable to switch the encoding” error when inserting XML into SQL Server

Question

I\'m trying to insert into XML column (SQL SERVER 2008 R2), but the server\'s complaining:

System.Data.SqlClient.SqlException (0x80131904):
XML

Answer 1

Although a .net string is always UTF-16 you need to serialize the object using UTF-16 encoding. That sould be something like this:

public static string ToString(object source, Type type, Encoding encoding)
{
    // The string to hold the object content
    String content;

    // Create a memoryStream into which the data can be written and readed
    using (var stream = new MemoryStream())
    {
        // Create the xml serializer, the serializer needs to know the type
        // of the object that will be serialized
        var xmlSerializer = new XmlSerializer(type);

        // Create a XmlTextWriter to write the xml object source, we are going
        // to define the encoding in the constructor
        using (var writer = new XmlTextWriter(stream, encoding))
        {
            // Save the state of the object into the stream
            xmlSerializer.Serialize(writer, source);

            // Flush the stream
            writer.Flush();

            // Read the stream into a string
            using (var reader = new StreamReader(stream, encoding))
            {
                // Set the stream position to the begin
                stream.Position = 0;

                // Read the stream into a string
                content = reader.ReadToEnd();
            }
        }
    }

    // Return the xml string with the object content
    return content;
}

By setting the encoding to Encoding.Unicode not only the string will be UTF-16 but you should also get the xml string as UTF-16.