使用 FastMember 递归复制属性

Question

我有两个来自这个类的对象：

public class A
{
    public int Id { get; set; }
    public string Name { get; set; }
    public IList<B> Bs { get; set; }
}

public class B
{
    public string Description { get; set; }
    public IList<C> Cs { get; set; }
}

public class C
{
    public string Description { get; set; }
}

现在我想用 FastMember 遍历两个对象实例的所有属性，并将属性从 object 1 复制到 object 2。

这是我到目前为止得到的（不工作！）

// Set accessors
var sourceAccessor = ObjectAccessor.Create(object1);
var targetAccessor = ObjectAccessor.Create(object2);

foreach (var sourceItem in (IList)sourceAccessor.Target)
{
    var targetItemAccessor = ObjectAccessor.Create(targetAccessor.Target);
    var sourceItemAccessor = ObjectAccessor.Create(sourceItem);

    // Overwrite property
    targetItemAccessor[p] = sourceItemAccessor[p];
}

这段代码显然不起作用...有什么想法吗？谢谢！

Answer 1

您可以在TypeAccessor 的帮助下创建一个shallow copy，使用类似：

var sourceAccessor = ObjectAccessor.Create(object1);
var targetAccessor = ObjectAccessor.Create(object2);

var access = TypeAccessor.Create(typeof(A));
var members = access.GetMembers();

foreach (var member in members)
{
    targetAccessor[member.Name] = sourceAccessor[member.Name];
}

查看FastMember tests 的用法示例。

对于深拷贝，您可以检查属性名称或使用property type 来确定是应用deep copy of lists 还是浅拷贝就足够了。

编辑：这是一个简化版本的示例，它递归复制IList 类型的属性（请参阅此question，了解如何确定哪个属性是列表），假设源对象和目标对象的列表具有相同的长度：

private static void MirrorObject(object object1, object object2)
{
    var sourceAccessor = ObjectAccessor.Create(object1);
    var targetAccessor = ObjectAccessor.Create(object2);

    var access = TypeAccessor.Create(object1.GetType());
    var members = access.GetMembers();

    foreach (var member in members)
    {
        if (member.Type.IsGenericType && (member.Type.GetGenericTypeDefinition() == typeof(IList<>)))
        {
            var list1 = (IList)sourceAccessor[member.Name];
            var list2 = (IList)targetAccessor[member.Name];
            if (list1.Count != list2.Count)
            {
                throw new ArgumentException("Lists need to be of the same length.");
            }
            for (var i = 0; i < list1.Count; ++i)
            {
                MirrorObject(list1[i], list2[i]);
            }
        }
        else
        {
            targetAccessor[member.Name] = sourceAccessor[member.Name];
        }
    }
}