C# 对象深度拷贝
转载
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Reflection.Emit;
using System.Text; namespace Care.Common
{
public static class ObjectCopy
{
struct Identity
{
int _hashcode;
RuntimeTypeHandle _type; public Identity(int hashcode, RuntimeTypeHandle type)
{
_hashcode = hashcode;
_type = type;
}
}
//缓存对象复制的方法。
static Dictionary<Type, Func<object, Dictionary<Identity, object>, object>> methods1 = new Dictionary<Type, Func<object, Dictionary<Identity, object>, object>>();
static Dictionary<Type, Action<object, Dictionary<Identity, object>, object>> methods2 = new Dictionary<Type, Action<object, Dictionary<Identity, object>, object>>(); static List<FieldInfo> GetSettableFields(Type t)
{
return t.GetFields(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance).ToList();
} static Func<object, Dictionary<Identity, object>, object> CreateCloneMethod1(Type type, Dictionary<Identity, object> objects)
{
Type tmptype;
var fields = GetSettableFields(type);
var dm = new DynamicMethod(string.Format("Clone{0}", Guid.NewGuid()), typeof(object), new[] { typeof(object), typeof(Dictionary<Identity, object>) }, true);
var il = dm.GetILGenerator();
il.DeclareLocal(type);
il.DeclareLocal(type);
il.DeclareLocal(typeof(Identity));
if (!type.IsArray)
{
il.Emit(OpCodes.Newobj, type.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null));
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc_1);
il.Emit(OpCodes.Ldloca_S, );
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Castclass, type);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc_0);
il.Emit(OpCodes.Callvirt, typeof(object).GetMethod("GetHashCode"));
il.Emit(OpCodes.Ldtoken, type);
il.Emit(OpCodes.Call, typeof(Identity).GetConstructor(BindingFlags.Instance | BindingFlags.Public, null, new[] { typeof(int), typeof(RuntimeTypeHandle) }, null));
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldloc_2);
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Callvirt, typeof(Dictionary<Identity, object>).GetMethod("Add"));
foreach (var field in fields)
{
if (!field.FieldType.IsValueType && field.FieldType != typeof(String))
{
//不符合条件的字段，直接忽略，避免报错。
if ((field.FieldType.IsArray && (field.FieldType.GetArrayRank() > || (!(tmptype = field.FieldType.GetElementType()).IsValueType && tmptype != typeof(String) && tmptype.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))) ||
(!field.FieldType.IsArray && field.FieldType.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))
break;
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Ldarg_1);
il.EmitCall(OpCodes.Call, typeof(ObjectCopy).GetMethod("CopyImpl", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod(field.FieldType), null);
il.Emit(OpCodes.Stfld, field);
}
else
{
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Stfld, field);
}
}
for (type = type.BaseType; type != null && type != typeof(object); type = type.BaseType)
{
//只需要查找基类的私有成员，共有或受保护的在派生类中直接被复制过了。
fields = type.GetFields(BindingFlags.NonPublic | BindingFlags.Instance).ToList();
foreach (var field in fields)
{
if (!field.FieldType.IsValueType && field.FieldType != typeof(String))
{
//不符合条件的字段，直接忽略，避免报错。
if ((field.FieldType.IsArray && (field.FieldType.GetArrayRank() > || (!(tmptype = field.FieldType.GetElementType()).IsValueType && tmptype != typeof(String) && tmptype.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))) ||
(!field.FieldType.IsArray && field.FieldType.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))
break;
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Ldarg_1);
il.EmitCall(OpCodes.Call, typeof(ObjectCopy).GetMethod("CopyImpl", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod(field.FieldType), null);
il.Emit(OpCodes.Stfld, field);
}
else
{
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Stfld, field);
}
}
}
}
else
{
Type arraytype = type.GetElementType();
var i = il.DeclareLocal(typeof(int));
var lb1 = il.DefineLabel();
var lb2 = il.DefineLabel();
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Castclass, type);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc_0);
il.Emit(OpCodes.Ldlen);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Ldc_I4_1);
il.Emit(OpCodes.Sub);
il.Emit(OpCodes.Stloc, i);
il.Emit(OpCodes.Newarr, arraytype);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc_1);
il.Emit(OpCodes.Ldloca_S, );
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Callvirt, typeof(object).GetMethod("GetHashCode"));
il.Emit(OpCodes.Ldtoken, type);
il.Emit(OpCodes.Call, typeof(Identity).GetConstructor(BindingFlags.Instance | BindingFlags.Public, null, new[] { typeof(int), typeof(RuntimeTypeHandle) }, null));
il.Emit(OpCodes.Ldarg_1);
il.Emit(OpCodes.Ldloc_2);
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Callvirt, typeof(Dictionary<Identity, object>).GetMethod("Add"));
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Br, lb1);
il.MarkLabel(lb2);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Ldelem, arraytype);
if (!arraytype.IsValueType && arraytype != typeof(String))
{
il.EmitCall(OpCodes.Call, typeof(ObjectCopy).GetMethod("CopyImpl", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod(arraytype), null);
}
il.Emit(OpCodes.Stelem, arraytype);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Ldc_I4_1);
il.Emit(OpCodes.Sub);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc, i);
il.MarkLabel(lb1);
il.Emit(OpCodes.Ldc_I4_0);
il.Emit(OpCodes.Clt);
il.Emit(OpCodes.Brfalse, lb2);
}
il.Emit(OpCodes.Ret); return (Func<object, Dictionary<Identity, object>, object>)dm.CreateDelegate(typeof(Func<object, Dictionary<Identity, object>, object>));
} static Action<object, Dictionary<Identity, object>, object> CreateCloneMethod2(Type type, Dictionary<Identity, object> objects)
{
Type tmptype;
var fields = GetSettableFields(type);
var dm = new DynamicMethod(string.Format("Copy{0}", Guid.NewGuid()), null, new[] { typeof(object), typeof(Dictionary<Identity, object>), typeof(object) }, true);
var il = dm.GetILGenerator();
il.DeclareLocal(type);
il.DeclareLocal(type);
il.DeclareLocal(typeof(Identity));
if (!type.IsArray)
{
il.Emit(OpCodes.Ldarg_2);
il.Emit(OpCodes.Castclass, type);
il.Emit(OpCodes.Stloc_1);
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Castclass, type);
il.Emit(OpCodes.Stloc_0);
foreach (var field in fields)
{
if (!field.FieldType.IsValueType && field.FieldType != typeof(String))
{
//不符合条件的字段，直接忽略，避免报错。
if ((field.FieldType.IsArray && (field.FieldType.GetArrayRank() > || (!(tmptype = field.FieldType.GetElementType()).IsValueType && tmptype != typeof(String) && tmptype.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))) ||
(!field.FieldType.IsArray && field.FieldType.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))
break;
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Ldarg_1);
il.EmitCall(OpCodes.Call, typeof(ObjectCopy).GetMethod("CopyImpl", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod(field.FieldType), null);
il.Emit(OpCodes.Stfld, field);
}
else
{
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Stfld, field);
}
}
for (type = type.BaseType; type != null && type != typeof(object); type = type.BaseType)
{
//只需要查找基类的私有成员，共有或受保护的在派生类中直接被复制过了。
fields = type.GetFields(BindingFlags.NonPublic | BindingFlags.Instance).ToList();
foreach (var field in fields)
{
if (!field.FieldType.IsValueType && field.FieldType != typeof(String))
{
//不符合条件的字段，直接忽略，避免报错。
if ((field.FieldType.IsArray && (field.FieldType.GetArrayRank() > || (!(tmptype = field.FieldType.GetElementType()).IsValueType && tmptype != typeof(String) && tmptype.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))) ||
(!field.FieldType.IsArray && field.FieldType.GetConstructor(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null) == null))
break;
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Ldarg_1);
il.EmitCall(OpCodes.Call, typeof(ObjectCopy).GetMethod("CopyImpl", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod(field.FieldType), null);
il.Emit(OpCodes.Stfld, field);
}
else
{
il.Emit(OpCodes.Ldloc_1);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldfld, field);
il.Emit(OpCodes.Stfld, field);
}
}
}
}
else
{
Type arraytype = type.GetElementType();
var i = il.DeclareLocal(typeof(int));
var lb1 = il.DefineLabel();
var lb2 = il.DefineLabel();
il.Emit(OpCodes.Ldarg_0);
il.Emit(OpCodes.Castclass, type);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc_0);
il.Emit(OpCodes.Ldlen);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Ldc_I4_1);
il.Emit(OpCodes.Sub);
il.Emit(OpCodes.Stloc, i);
il.Emit(OpCodes.Ldarg_2);
il.Emit(OpCodes.Castclass, type);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc_1);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Br, lb1);
il.MarkLabel(lb2);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Ldloc_0);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Ldelem, arraytype);
if (!arraytype.IsValueType && arraytype != typeof(String))
{
il.EmitCall(OpCodes.Call, typeof(ObjectCopy).GetMethod("CopyImpl", BindingFlags.NonPublic | BindingFlags.Static).MakeGenericMethod(arraytype), null);
}
il.Emit(OpCodes.Stelem, arraytype);
il.Emit(OpCodes.Ldloc, i);
il.Emit(OpCodes.Ldc_I4_1);
il.Emit(OpCodes.Sub);
il.Emit(OpCodes.Dup);
il.Emit(OpCodes.Stloc, i);
il.MarkLabel(lb1);
il.Emit(OpCodes.Ldc_I4_0);
il.Emit(OpCodes.Clt);
il.Emit(OpCodes.Brfalse, lb2);
}
il.Emit(OpCodes.Ret); return (Action<object, Dictionary<Identity, object>, object>)dm.CreateDelegate(typeof(Action<object, Dictionary<Identity, object>, object>));
} static T CopyImpl<T>(T source, Dictionary<Identity, object> objects) where T : class
{
//为空则直接返回null
if (source == null)
return null; Type type = source.GetType();
Identity id = new Identity(source.GetHashCode(), type.TypeHandle);
object result;
//如果发现曾经复制过，用之前的，从而停止递归复制。
if (!objects.TryGetValue(id, out result))
{
//最后查找对象的复制方法，如果不存在，创建新的。
Func<object, Dictionary<Identity, object>, object> method;
if (!methods1.TryGetValue(type, out method))
{
method = CreateCloneMethod1(type, objects);
methods1.Add(type, method);
}
result = method(source, objects);
}
return (T)result;
} /// <summary>
/// 创建对象深度复制的副本
/// </summary>
public static T ToObjectCopy<T>(this T source) where T : class
{
Type type = source.GetType();
Dictionary<Identity, object> objects = new Dictionary<Identity, object>();//存放内嵌引用类型的复制链，避免构成一个环。
Func<object, Dictionary<Identity, object>, object> method;
if (!methods1.TryGetValue(type, out method))
{
method = CreateCloneMethod1(type, objects);
methods1.Add(type, method);
}
return (T)method(source, objects);
} /// <summary>
/// 将source对象的所有属性复制到target对象中，深度复制
/// </summary>
public static void ObjectCopyTo<T>(this T source, T target) where T : class
{
if (target == null)
throw new Exception("将要复制的目标未初始化");
Type type = source.GetType();
if (type != target.GetType())
throw new Exception("要复制的对象类型不同，无法复制");
Dictionary<Identity, object> objects = new Dictionary<Identity, object>();//存放内嵌引用类型的复制链，避免构成一个环。
objects.Add(new Identity(source.GetHashCode(), type.TypeHandle), source);
Action<object, Dictionary<Identity, object>, object> method;
if (!methods2.TryGetValue(type, out method))
{
method = CreateCloneMethod2(type, objects);
methods2.Add(type, method);
}
method(source, objects, target);
}
}
}
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