C# 实体类几种深拷贝的方法——解决关于对象赋值，A=B，A改变，B也改变问题

几种常见的深拷贝方式

1、利用反射实现

public static T DeepCopyByReflection<T>(T obj)
{
if (obj is string || obj.GetType().IsValueType)
return obj;

　　object retval = Activator.CreateInstance(obj.GetType());
FieldInfo[] fields = obj.GetType().GetFields(BindingFlags.Public|BindingFlags.NonPublic|BindingFlags.Static|BindingFlags.Instance);
foreach(var field in fields)
{
try
{
field.SetValue(retval, DeepCopyByReflection(field.GetValue(obj)));
}
catch { }
}

　　return (T)retval;
}

2、利用二进制序列化和反序列化

public static T DeepCopyByBinary<T>(T obj)
{
object retval;
using (MemoryStream ms = new MemoryStream())
{
BinaryFormatter bf = new BinaryFormatter();
bf.Serialize(ms, obj);
ms.Seek(0, SeekOrigin.Begin);
retval = bf.Deserialize(ms);
ms.Close();
}
return (T)retval;
}

注意，使用二进制序列化和反序列化时，在需要序列化的类上要加上[Serializable]

[Serializable]
public class Person
{
public string Name { get; set; }
}

3、利用xml序列化和反序列化

public static T DeepCopyByXml<T>(T obj)
{
object retval;
using (MemoryStream ms = new MemoryStream())
{
XmlSerializer xml=new XmlSerializer(typeof(T));
xml.Serialize(ms, obj);
ms.Seek(0, SeekOrigin.Begin);
retval = xml.Deserialize(ms);
ms.Close();
}
return (T)retval;
}