Question

是否可以在Windows Phone 7/8上使用protobuf-net序列化/反序列化类型？
我已经尝试了下面的代码，似乎不支持Constructor跳过（即UseConstructor = false）所以我创建了一个无参数构造函数，但反序列化失败，“尝试访问该方法失败：Wp7Tests.ImmutablePoint.set_X（System.Double））“

public class ImmutablePoint
{
    public double X { get; private set; }
    public double Y { get; private set; }
    public ImmutablePoint() {}

    public ImmutablePoint(double x, double y)
    {
        X = x;
        Y = y;
    }
}
public sub Test()
{
        ImmutablePoint pt = new ImmutablePoint(1, 2);
        var model = TypeModel.Create();
        var ptType = model.Add(typeof(ImmutablePoint), false);
        ptType.AddField(1, "X");
        ptType.AddField(2, "Y");
        IsolatedStorageFile store = IsolatedStorageFile.GetUserStoreForApplication();

        using (var stream1 = new IsolatedStorageFileStream("test.bin", FileMode.Create, store))
        {
            try
            {
                model.Serialize(stream1, pt);
            }
            catch (Exception e)
            {                    
                Debugger.Break();
            }
        }
        const double EPSILON = 0.001;
        using (var stream1 = new IsolatedStorageFileStream("test.bin", FileMode.Open, store))
        {
            try
            {
                ImmutablePoint ptDeSer = (ImmutablePoint) model.Deserialize(stream1,null, typeof(ImmutablePoint));
                Debug.Assert(Math.Abs(pt.X - ptDeSer.X) < EPSILON);
                Debug.Assert(Math.Abs(pt.Y - ptDeSer.Y) < EPSILON);
            }
            catch (Exception e)
            {
                Debugger.Break();
            }
        }
}

Answer 1

您可以使用代理;这里我用属性装饰它，但它也可以手动配置：

[ProtoContract]
public class MutablePoint {
    [ProtoMember(1)] public double X { get; set; }
    [ProtoMember(2)] public double Y { get; set; }

    public static implicit operator MutablePoint(ImmutablePoint value) {
        return value == null ? null : new MutablePoint {X=value.X, Y=value.Y};
    }
    public static implicit operator ImmutablePoint(MutablePoint value) {
        return value == null ? null : new ImmutablePoint(value.X, value.Y);
    }
}

然后告诉模型在看到ImmutablePoint时使用它：

var model = TypeModel.Create();
model.Add(typeof(MutablePoint), true);
model.Add(typeof(ImmutablePoint), false).SetSurrogate(typeof(MutablePoint));

序列化器将根据需要使用运算符在它们之间切换。序列化程序将使用implicit或explicit自定义转换运算符。

编辑：像这样反序列化

ImmutablePoint ptDeSer = (ImmutablePoint)model.Deserialize(stream1, null, typeof(ImmutablePoint));

Answer 2

这在Windows Phone上无法实现。反序列化程序无法访问setter并使用反射访问私有成员会导致Windows Phone上出现MemberAccessException。我能想到让这样的东西工作的唯一方法是创建一个序列化的包装器，然后可以调用你的ImmutablePoint的构造函数。这有点乱，因为包装类需要X和Y的公共读写属性。

您还可以查看使用InternalsVisibleTo属性来允许序列化程序访问属性（假设您将setter从private更改为internal）。虽然还是凌乱......

是否可以在Windows Phone 7/8上使用protobuf-net序列化/反序列化不可变类型？

2 个答案: