WeakReference.cs

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using System.Diagnostics.CodeAnalysis;
using System.Runtime.CompilerServices;
using System.Runtime.Serialization;
 
namespace System;
 
[Serializable]
[TypeForwardedFrom("mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089")]
public class WeakReference : ISerializable
{
    internal IntPtr m_handle;
 
    public virtual extern bool IsAlive
    {
        [MethodImpl(MethodImplOptions.InternalCall)]
        get;
    }
 
    public virtual bool TrackResurrection => IsTrackResurrection();
 
    public virtual extern object? Target
    {
        [MethodImpl(MethodImplOptions.InternalCall)]
        get;
        [MethodImpl(MethodImplOptions.InternalCall)]
        set;
    }
 
    protected WeakReference()
    {
        throw new NotImplementedException();
    }
 
    [MethodImpl(MethodImplOptions.InternalCall)]
    extern ~WeakReference();
 
    [MethodImpl(MethodImplOptions.InternalCall)]
    private extern void Create(object target, bool trackResurrection);
 
    [MethodImpl(MethodImplOptions.InternalCall)]
    private extern bool IsTrackResurrection();
 
    public WeakReference(object? target)
        : this(target, trackResurrection: false)
    {
    }
 
    public WeakReference(object? target, bool trackResurrection)
    {
        Create(target, trackResurrection);
    }
 
    protected WeakReference(SerializationInfo info, StreamingContext context)
    {
        if (info == null)
        {
            throw new ArgumentNullException("info");
        }
        object value = info.GetValue("TrackedObject", typeof(object));
        bool boolean = info.GetBoolean("TrackResurrection");
        Create(value, boolean);
    }
 
    public virtual void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        if (info == null)
        {
            throw new ArgumentNullException("info");
        }
        info.AddValue("TrackedObject", Target, typeof(object));
        info.AddValue("TrackResurrection", IsTrackResurrection());
    }
}
[Serializable]
[TypeForwardedFrom("mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089")]
public sealed class WeakReference<T> : ISerializable where T : class?
{
    internal IntPtr m_handle;
 
    private extern T Target
    {
        [MethodImpl(MethodImplOptions.InternalCall)]
        [return: MaybeNull]
        get;
        [MethodImpl(MethodImplOptions.InternalCall)]
        set;
    }
 
    public void SetTarget(T target)
    {
        Target = target;
    }
 
    [MethodImpl(MethodImplOptions.InternalCall)]
    extern ~WeakReference();
 
    [MethodImpl(MethodImplOptions.InternalCall)]
    private extern void Create(T target, bool trackResurrection);
 
    [MethodImpl(MethodImplOptions.InternalCall)]
    private extern bool IsTrackResurrection();
 
    public WeakReference(T target)
        : this(target, trackResurrection: false)
    {
    }
 
    public WeakReference(T target, bool trackResurrection)
    {
        Create(target, trackResurrection);
    }
 
    private WeakReference(SerializationInfo info, StreamingContext context)
    {
        if (info == null)
        {
            throw new ArgumentNullException("info");
        }
        T target = (T)info.GetValue("TrackedObject", typeof(T));
        bool boolean = info.GetBoolean("TrackResurrection");
        Create(target, boolean);
    }
 
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public bool TryGetTarget([MaybeNullWhen(false)][NotNullWhen(true)] out T target)
    {
        return (target = Target) != null;
    }
 
    public void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        if (info == null)
        {
            throw new ArgumentNullException("info");
        }
        info.AddValue("TrackedObject", Target, typeof(T));
        info.AddValue("TrackResurrection", IsTrackResurrection());
    }
}