深度克隆对象

深度克隆对象

虽然标准做法是实现

ICloneable

接口（在此进行描述，所以我不会反驳），但这是我之前在The Code
Project
上发现的一个不错的深克隆对象复印机，并将其合并到我们的资料中。

如在其他地方提到的，它确实要求您的对象可序列化。

using System;using System.IO;using System.Runtime.Serialization;using System.Runtime.Serialization.Formatters.Binary;/// <summary>/// Reference Article http://www.preproject.com/KB/tips/SerializedObjectCloner.aspx/// Provides a method for performing a deep copy of an object./// Binary Serialization is used to perform the copy./// </summary>public static class ObjectCopier{    /// <summary>    /// Perform a deep Copy of the object.    /// </summary>    /// <typeparam name="T">The type of object being copied.</typeparam>    /// <param name="source">The object instance to copy.</param>    /// <returns>The copied object.</returns>    public static T Clone<T>(T source)    {        if (!typeof(T).IsSerializable)        { throw new ArgumentException("The type must be serializable.", nameof(source));        }        // Don't serialize a null object, simply return the default for that object        if (Object.ReferenceEquals(source, null))        { return default(T);        }        IFormatter formatter = new BinaryFormatter();        Stream stream = new MemoryStream();        using (stream)        { formatter.Serialize(stream, source); stream.Seek(0, SeekOrigin.Begin); return (T)formatter.Deserialize(stream);        }    }}

这个想法是先序列化您的对象，然后反序列化为一个新的对象。这样做的好处是，当对象变得太复杂时，您不必担心克隆所有内容。

并使用扩展方法（也来自最初引用的源）：

如果您更喜欢使用C＃3.0
的新扩展方法，请将方法更改为具有以下签名：

public static T Clone<T>(this T source){   //...}

现在，方法调用简单地变为

objectBeingCloned.Clone();

。

编辑
（2015年1月10日）以为我会重新审视此事，我最近提到开始使用（Newtonsoft）Json来做到这一点，它应该更轻巧，并且避免了[Serializable]标签的开销。（ NB @atconway在注释中指出，不使用JSON方法克隆私有成员）

/// <summary>/// Perform a deep Copy of the object, using Json as a serialisation method. NOTE: Private members are not cloned using this method./// </summary>/// <typeparam name="T">The type of object being copied.</typeparam>/// <param name="source">The object instance to copy.</param>/// <returns>The copied object.</returns>public static T CloneJson<T>(this T source){     // Don't serialize a null object, simply return the default for that object    if (Object.ReferenceEquals(source, null))    {        return default(T);    }    // initialize inner objects individually    // for example in default constructor some list property initialized with some values,    // but in 'source' these items are cleaned -    // without ObjectCreationHandling.Replace default constructor values will be added to result    var deserializeSettings = new JsonSerializerSettings {ObjectCreationHandling = ObjectCreationHandling.Replace};    return JsonConvert.DeserializeObject<T>(JsonConvert.SerializeObject(source), deserializeSettings);}