Why does SerializationInfo not have TryGetValue methods?

In addition to the enumerating solution, there is an internal method SerializationInfo.GetValueNoThrow() according to the Reference Source.

You can e.g. make an extension method like this and avoid the exception overhead:

static class SerializationInfoExtensions
{
    private static MethodInfo _GetValueNoThrow =
        typeof(SerializationInfo).GetMethod("GetValueNoThrow",
                                            BindingFlags.Instance | BindingFlags.NonPublic);

    public static Object GetValueNoThrow(this SerializationInfo info, String name, Type type)
    {
        return _GetValueNoThrow.Invoke(info, new object[] { name, type });
    }
}

This solution still results in some reflection overhead compared to a plain method call, but it is an order of magnitude smaller – a crude benchmark at .NET Fiddle:

---

However, it should be noted that the whole SerializationInfo type is going to be deprecated in a future version of .NET, as discussed in Add SerializationInfo.TryGetValue API #42460.

You can iterate over the available fields and use switch, though...

foreach(SerializationEntry entry in info) {
    switch(entry.Name) {
        ...
    }
}

Or you could use protobuf-net ;-p

Well no one answered 'why', but I'm guessing that's addressed to MS..

My implementation for anyone in need:

public static class SerializationInfoExtensions
{
    public static bool TryGetValue<T>(this SerializationInfo serializationInfo, string name, out T value)
    {
        try
        {
            value = (T) serializationInfo.GetValue(name, typeof(T));
            return true;
        }
        catch (SerializationException)
        {
            value = default(T);
            return false;
        }
    }

    public static T GetValueOrDefault<T>(this SerializationInfo serializationInfo, string name, Lazy<T> defaultValue)
    {
        try
        {
            return (T) serializationInfo.GetValue(name, typeof(T));
        }
        catch (SerializationException)
        {
            return defaultValue.Value;
        }
    }
}