启动时加载时反序列化导致InvalidOperationException

我有一个类,可以在我的WPF应用程序加载后轻松地序列化和反序列化。我现在正试图添加在传入项目文件时在启动时加载项目的功能。不幸的是,它正在引发InvalidOperationException,声明:

There is an error in XML document (2, 2). ---> System.InvalidOperationException: <WeightingParametersBit xmlns=''> was not expected.

这个 WeightingParametersBit 是我试图序列化的类的成员的类型。它基本上只是一个字典的容器。奇怪的是,文件不包含 <WeightingParametersBit xmlns=.... 文件中的任何地方。一旦抛出此异常并启动应用程序。如果单击“加载”按钮并选择同一个项目文件,则加载效果会很好。

public class WeightSettings
{
    public double UserScoreSlagging;
    public double UserScoreFouling;
    public WeightMode BitWeightMode = WeightMode.Manual;
    public WeightMode LigWeightMode = WeightMode.Manual;
    public WeightingParametersBit BitWeights = new WeightingParametersBit();
    public WeightingParametersLig LigWeights = new WeightingParametersLig();
}

下面是它生成的xml(为了查看目的而缩减):

<?xml version="1.0" encoding="utf-8"?>
<WeightSettings>
    <UserScoreSlagging>0</UserScoreSlagging>
    <UserScoreFouling>0</UserScoreFouling>
    <BitWeightMode>Manual</BitWeightMode>
    <LigWeightMode>Manual</LigWeightMode>
    <BitWeights>
        <bituminous>
            ...
        </bituminous>
    </BitWeights>
    <LigWeights>
        <lignitic>
          ...
        </lignitic>
    </LigWeights>
</WeightSettings>

我的泛型序列化代码:

public static void Serialize<T>(this T source, TextWriter writer)
{
    // Don't serialize a null object
    if (Object.ReferenceEquals(source, null))
    {
        throw new ArgumentException("Trying to serialize null object.", "source");
    }

    XmlSerializer s = new XmlSerializer(typeof(T));
    s.Serialize(writer, source);
    writer.WriteLine();
}

反序列化代码:

public static T Deserialize<T>(this T source, TextReader reader)
{
    XmlSerializer s = new XmlSerializer(typeof(T));
    source = (T)s.Deserialize(reader);
    return source;
}

对反序列化的调用来自名为 WeightSettings 权重设置 )不为空:

WeightSettings = WeightSettings.Deserialize(sr);

我怎样才能纠正这种行为?或许更重要的是:为什么我只在加载了窗口的事件上看到这种行为?