/// <summary>
/// Creates a deep copy of an object using the supplied dictionary of visited objects as
/// a source of objects already encountered in the copy traversal. The dictionary of visited
/// objects is used for holding objects that have already been copied, to avoid erroneous
/// duplication of parts of the object graph.
/// </summary>
/// <param name="instance">The object to be copied.</param>
/// <param name="visited">The graph of objects visited so far.</param>
/// <returns></returns>
private static object Clone(this object instance, VisitedGraph visited)
{
if (instance == null)
{
return(null);
}
Type instanceType = instance.GetType();
if (instanceType.IsValueType || instanceType == typeof(string))
{
return(instance); // Value types and strings are immutable
}
else if (instanceType.IsArray)
{
int length = ((Array)instance).Length;
Array copied = (Array)Activator.CreateInstance(instanceType, length);
visited.Add(instance, copied);
for (int i = 0; i < length; ++i)
{
copied.SetValue(((Array)instance).GetValue(i).Clone(visited), i);
}
return(copied);
}
else
{
return(Clone(instance, visited, InstanceCreator.GetInstance(instanceType)));
}
}
/// <summary>
/// Creates a copy of the object.
/// </summary>
/// <param name="instance">The object to be copied.</param>
/// <returns>A deep copy of the object.</returns>
public static object Copy(this object instance)
{
if (instance == null)
{
return(null);
}
var copy = InstanceCreator.GetInstance(instance.GetType());
Copy(instance, copy);
return(copy);
}
/// <summary>
/// Creates a copy of the object.
/// </summary>
/// <param name="instance">The object to be copied.</param>
/// <returns>A deep copy of the object.</returns>
public static object Copy(this object instance)
{
if (instance == null)
{
return(null);
}
var copy = InstanceCreator.GetInstance(instance.GetType());
Copy(instance, copy);
//var ser1 = Serialize(instance);
//var ser2 = Serialize(copy);
//if (!CompareMemoryStreams(ser1, ser2))
//{
// var co = new CompareObjects();
// co.CompareChildren = true;
// co.ComparePrivateFields = true;
// co.ComparePrivateProperties = true;
// co.Compare(instance, copy);
// throw new InvalidOperationException(co.DifferencesString);
//}
return(copy);
}
