获取C＃中嵌套对象的字段的完整路径

Question

Lets say we have two classes:

public class MyClass
{
    public MyClass2 Foo { get; set; }
}

public class MyClass2
{
    public int Blah { get; set; }
}

I would like to display the full path to the Blah property but without including the namespace, so in this case, the expected result would be:

MyClass.Foo.Blah

I've run the stuff in the debug mode and dag in the MyClass object using reflection typeof(MyClass) . In the end, I found the Blah property in the tree using the expression:

((System.Reflection.PropertyInfo[])((System.Reflection.TypeInfo)((System.Reflection.RuntimeMethodInfo)((System.Reflection.MemberInfo[])((System.Reflection.TypeInfo)((System.Reflection.RuntimeFieldInfo)((System.Reflection.FieldInfo[])((System.Reflection.TypeInfo)typeof(MyClass)).DeclaredFields)[0]).DeclaringType).DeclaredMembers)[0]).ReturnType).DeclaredProperties)[0]

which looks a bit clunky. Anybody knows some "smart" way how can I receive the result but without hardcoding the names of the fields? Cheers

Answer 1

the simplest way I can think of is

Type cType = typeof(MyClass);
var prop = cType.GetProperties()[0];
var innerPropName = prop.PropertyType.GetProperties()[0].Name;
Console.WriteLine($"{nameof(MyClass)}.{prop.Name}.{innerPropName}");

---

Edit

I have used recursive function in order to be able to loop through the Properties

public static string GetClassDetails(Type t, ref IList<string> sList, string str = null )
{
    if (sList is null) sList = new List<string>();
    if (str is null) str = t.Name;

    foreach (var propertyInfo in t.GetProperties())
    {
        str = $"{str}.{propertyInfo.Name}";
        if (propertyInfo.PropertyType.IsClass)
            str = $"{str}.{GetClassDetails(propertyInfo.PropertyType, ref sList, str)}";

        sList.Add(str);
        str = "";
    }

    return str;
}

You can call it

 IList<string> sList = null;
 var result = GetClassDetails(cType, ref sList);

Example Class

public class MyClass
{
    public MyClass2 Foo { get; set; }
    public int Baz { get; set; }
}

public class MyClass2
{
    public int Blah { get; set; }
}

Answer 2

You can use ToString method of an expression to get the path. Minimal modification is needed to replace the lambda part ( x => x ) with YourClassName :

usage: ReflectionHelper<MyClass>.GetPath(x => x.Foo.Blah) // -> "MyClass.Foo.Blah"

public class ReflectionHelper<T>
{
    public static string GetPath<TProperty>(Expression<Func<T, TProperty>> expr)
    {
        var name = expr.Parameters[0].Name;

        return expr.ToString()
            .Replace($"{name} => {name}", typeof(T).Name);
    }
}