Question

我看过几个问题但没有一个答案有帮助。我尝试使用多个流对象（StreamWriter，FileStream）。我尝试使用XmlWriter，XmlSerializer等。

这是我的代码：

namespace FacebookPlusPlus
{
    internal static class AppConfig
    {
        public static string AccessToken
        {
            get { return s_SerializableConfig.m_AccessToken; }
            set { s_SerializableConfig.m_AccessToken = value; }
        }

        public static bool AutoConnect
        {
            get { return s_SerializableConfig.m_AutoConnect; }
            set { s_SerializableConfig.m_AutoConnect = value; }
        }

        public static string ErrorMessage { get; set; }

        private const string k_ConfigFilePath = "AppConfig.xml";
        private static SerializableConfig s_SerializableConfig = new SerializableConfig();

        [Serializable]
        public class SerializableConfig
        {
            public string m_AccessToken;
            public bool m_AutoConnect;
        }

        public static bool ExportConfig()
        {
            bool exportSucceed = false;
            try
            {
                using (StreamWriter writer = new StreamWriter(File.Open(k_ConfigFilePath, FileMode.Create)))
                {
                    XmlSerializer serializer = new XmlSerializer(s_SerializableConfig.GetType());
                    serializer.Serialize(writer, s_SerializableConfig);
                }

                exportSucceed = true;
            }
            catch (Exception exception)
            {
                ErrorMessage = exception.Message;
                if (File.Exists(k_ConfigFilePath))
                {
                    File.Delete(k_ConfigFilePath);
                }
            }

            return exportSucceed;
        }

        public static bool ImportConfig()
        {
            bool importSucceed = false;
            if (File.Exists(k_ConfigFilePath))
            {
                try
                {
                    using (Stream stream = File.Open(k_ConfigFilePath, FileMode.Open))
                    {
                        XmlSerializer serializer = new XmlSerializer(s_SerializableConfig.GetType());
                        s_SerializableConfig = (SerializableConfig)serializer.Deserialize(stream);
                    }

                    importSucceed = true;
                }
                catch (Exception exception)
                {
                    importSucceed = false;
                    ErrorMessage = exception.Message;
                }
            }

            return importSucceed;
        }
    }
}

这是一个例外：

There was an error generating the XML document.
   at System.Xml.Serialization.XmlSerializer.Serialize(XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, String encodingStyle, String id)
   at System.Xml.Serialization.XmlSerializer.Serialize(TextWriter textWriter, Object o, XmlSerializerNamespaces namespaces)
   at FacebookPlusPlus.AppConfig.ExportConfig() in c:\\...\\AppLogic\\AppConfig.cs:line 48

在发生错误时，字段AccessToken包含一个长字符串，AutoConnect包含true

Answer 1

当您调用Serealize方法时，您指定的第一个参数可能是问题的根本原因：

在xmlWriter参数中，指定派生自的对象抽象的XmlWriter类。 XmlTextWriter派生自的XmlWriter。

在您的情况下，您使用的是不是XmlWriter的StreamWriter。

来源：https://msdn.microsoft.com/en-us/library/10y9yyta(v=VS.110).aspx

编辑：既然你已经尝试了上述内容并且它对你的问题没有帮助，比如克里斯辛克莱说，试着获得内部异常。以下代码段可以提供帮助：

public void SerializeContainer( XmlWriter writer, Container obj )
{
  try
  {
    // Make sure even the construsctor runs inside a
    // try-catch block
    XmlSerializer ser = new XmlSerializer( typeof(Container));
    ser.Serialize( writer, obj );
  }
  catch( Exception ex )               
  {                                   
    DumpException( ex );             
  }                                   
}
public static void DumpException( Exception ex )
{
  Console.WriteLine( "--------- Outer Exception Data ---------" );        
  WriteExceptionInfo( ex );
  ex = ex.InnerException;                     
  if( null != ex )               
  {                                   
    Console.WriteLine( "--------- Inner Exception Data ---------" );                
    WriteExceptionInfo( ex.InnerException );    
    ex = ex.InnerException;
  }
}
public static void WriteExceptionInfo( Exception ex )
{
  Console.WriteLine( "Message: {0}", ex.Message );                  
  Console.WriteLine( "Exception Type: {0}", ex.GetType().FullName );
  Console.WriteLine( "Source: {0}", ex.Source );                    
  Console.WriteLine( "StrackTrace: {0}", ex.StackTrace );           
  Console.WriteLine( "TargetSite: {0}", ex.TargetSite );            
}

来源：https://msdn.microsoft.com/en-us/library/Aa302290.aspx

Answer 2

好的，我做了@dbc的建议并将AppConfig公开，删除了它的静态属性并隐藏了它的c'tor。效果很棒！

仍然对C＃奇怪的限制感到沮丧，这花了我几个小时来理解。并且我讨厌变通方法

namespace FacebookPlusPlus
{
    public class AppConfig
    {
        ...

        [Serializable]
        public class SerializableConfig
        {
            public string m_AccessToken;
            public bool m_AutoConnect;
        }

        private AppConfig() 
        {
            throw new InvalidOperationException("AppConfig Ctor Invoked");
        }

        ...
    }
}

将对象序列化为XML文件会引发异常

2 个答案: