namespace System { public class WeakReference : ISerializable { public virtual bool IsAlive { get; } public virtual object Target { get; set; } public virtual bool TrackResurrection { get; } public WeakReference(object target); public WeakReference(object target, bool trackResurrection); protected WeakReference(SerializationInfo info, StreamingContext context); public virtual void GetObjectData(SerializationInfo info, StreamingContext context); } }