C# 反射：获取类和基类的所有成员的信息

Question

当我运行以下代码时，它只返回MethodInfo / FieldInfo /etc。 直接属于我在其中搜索信息对象的Type 。我如何找到信息对象，而不管它驻留在基类中并且可能是私有的？

obj.GetType().GetMethod(methodName, bindingFlags);

Answer 1

好吧，你回答了你自己的问题，但据我所知，你的主要要求是How do I find the info object regardless of where it is found in the hierarchy?

此处不需要递归来获取完整层次结构中的所有成员。 您可以在Type上使用GetMembers函数，它将返回包括所有基类在内的所有成员。

下一个代码示例演示了这一点：

var names = 
    typeof(MyClass).GetMembers()
                   .Select (x => x.Name);

Console.WriteLine (string.Join(Environment.NewLine, names));

对于这样的结构

class MyClass : Base
{
    public string Name { get; set; }
    public string Surname { get; set; }
}

class Base
{
    public string Name { get; set; }
}

返回

get_Name
set_Name
get_Surname
set_Surname
get_Name
set_Name
ToString
Equals
GetHashCode
GetType
.ctor
Name
Surname

请注意，用于自动属性的get_Name访问器出现了两次，因为MyClass隐藏了基类的Name属性。 还要注意object类中定义的ToString 、 GetType等方法

Answer 2

如果在子类中找不到 info 对象，以下代码将查看对象的每个基类。 需要注意的是，虽然它会返回基类信息的对象，它将返回的对象，它“运行到第一个”，所以如果你有一个变量叫_blah在你的子类和可变称为_blah基类，那么_blah将从子类返回。

public static MethodInfo GetMethodInfo(this Type objType, string methodName, BindingFlags flags, bool isFirstTypeChecked = true)
{
    MethodInfo methodInfo = objType.GetMethod(methodName, flags);
    if (methodInfo == null && objType.BaseType != null)
    {
        methodInfo = objType.BaseType.GetMethodInfo(methodName, flags, false);
    }
    if (methodInfo == null && isFirstTypeChecked)
    {
        throw new MissingMethodException(String.Format("Method {0}.{1} could not be found with the following BindingFlags: {2}", objType.ReflectedType.FullName, methodName, flags.ToString()));
    }
    return methodInfo;
}

public static FieldInfo GetFieldInfo(this Type objType, string fieldName, BindingFlags flags, bool isFirstTypeChecked = true)
{
    FieldInfo fieldInfo = objType.GetField(fieldName, flags);
    if (fieldInfo == null && objType.BaseType != null)
    {
        fieldInfo = objType.BaseType.GetFieldInfo(fieldName, flags, false);
    }
    if (fieldInfo == null && isFirstTypeChecked)
    {
        throw new MissingFieldException(String.Format("Field {0}.{1} could not be found with the following BindingFlags: {2}", objType.ReflectedType.FullName, fieldName, flags.ToString()));
    }
    return fieldInfo;
}

Answer 3

我改变了 bsara 的实现，以便能够找到私有成员。

我像这样使用它：

public static void Save(string filename, object obj)
{
    try
    {
        using Stream s = new FileStream(filename, FileMode.Create, FileAccess.Write, FileShare.None);
        var b = new BinaryFormatter();
        b.Serialize(s, obj);
    }
    catch(SerializationException e)
    {
        var type= e.Message.Split("in Assembly")[0].Replace("Type", string.Empty).Replace("'", string.Empty).Trim();
        var assembly=e.Message.Split("in Assembly")[1].Split("'")[1];
        var atype= Type.GetType(type);

        string path = FindObject(new Stack<object>(new object[] { obj }), atype, "[myself]");

        throw new SerializationException($"Could not serialize path {path} in {obj.GetType().Name} due to not being able to process {type} from {assembly}. see inner exception for details", e);
    }            
}

小更新的方法：

private static bool TrySerialize(object obj)
{
    if(obj == null)
        return true;
    var stream = new MemoryStream();
    var bf = new BinaryFormatter();
    try
    {
        bf.Serialize(stream, obj);
    }
    catch(SerializationException)
    {
        return false;
    }
    return true;
}
private static string FindObject(Stack<object> self, Type typeToFind, string path)
{
    var _self = self.Peek();
    if(self.Where(x => x.Equals(_self)).Count() > 1) return null;
    foreach(var prop in _self.GetType().GetMembers(BindingFlags.Public | BindingFlags.Instance | BindingFlags.NonPublic).Where(x => !x.GetCustomAttributes(true).Any(y => y is XmlIgnoreAttribute)))
    {
        switch(prop.MemberType)
        {
            case System.Reflection.MemberTypes.Property:
                {
                    var line = string.Format("{0}::{1}", path, prop.Name);
                    var _prop = prop as PropertyInfo;

                    if(_prop.GetIndexParameters().Count() > 0) break;

                    if(typeToFind.IsAssignableFrom(_prop.PropertyType))
                        return line;


                    if(_prop.PropertyType.IsPrimitive || _prop.PropertyType == typeof(DateTime) || _prop.PropertyType == typeof(string))
                        continue;

                    var subInst = _prop.GetValue(_self, new object[0]);
                    if(subInst == null)
                        continue;

                    if(!TrySerialize(subInst))
                    {
                        System.Diagnostics.Debugger.Log(0, "", string.Format("Cannot serialize {0}\n", line));
                    }

                    self.Push(subInst);
                    var result = FindObject(self, typeToFind, line);
                    self.Pop();
                    if(result != null)
                        return result;
                }
                break;
            case System.Reflection.MemberTypes.Field:
                {
                    var line = string.Format("{0}::*{1}", path, prop.Name);
                    var _prop = prop as FieldInfo;

                    if(typeToFind.IsAssignableFrom(_prop.FieldType))
                        return line;

                    if(_prop.FieldType.IsPrimitive || _prop.FieldType == typeof(DateTime) || _prop.FieldType == typeof(string))
                        continue;

                    var subInst = _prop.GetValue(_self);
                    if(subInst == null)
                        continue;

                    if(!TrySerialize(subInst))
                    {
                        System.Diagnostics.Debugger.Log(0, "", string.Format("Cannot serialize field {0}\n", line));
                    }

                    self.Push(subInst);
                    var result = FindObject(self, typeToFind, line);
                    self.Pop();
                    if(result != null)
                        return result;
                }
                break;

            case System.Reflection.MemberTypes.Event:
                {
                    var line = string.Format("{0}::!{1}", path, prop.Name);
                    var _prop = prop as EventInfo;


                    if(typeToFind.IsAssignableFrom(_prop.EventHandlerType))
                        return line;

                    var field =  _self.GetType().GetField(_prop.Name,
                BindingFlags.NonPublic |BindingFlags.Instance |BindingFlags.GetField);


                    if(field != null && !field.GetCustomAttributes(true).Any(x => x is NonSerializedAttribute)  && !TrySerialize(field.GetValue(_self)))
                    {
                        System.Diagnostics.Debugger.Log(0, "", string.Format("Cannot serialize event {0}\n", line));
                    }


                }
                break;

            case System.Reflection.MemberTypes.Custom:
                {

                }
                break;
            default: break;
        }


    }
    if(_self is IEnumerable)
    {
        var list = (_self as IEnumerable).Cast<object>();
        var index = 0;
        foreach(var item in list)
        {
            index++;
            self.Push(item);
            var result = FindObject(self, typeToFind, string.Format("{0}[{1}]", path, index));
            self.Pop();
            if(result != null)
                return result;
        }
    }

    return null;
}