Question

I have a class which is marked with a custom attribute, like this:

public class OrderLine : Entity {     ...     [Parent]     public Order Order { get; set; }     public Address ShippingAddress{ get; set; }     ... } 

I want to write a generic method, where I need to get the Property on a Entity which is marked with the Parent attribute.

Here is my Attribute:

[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = false)] public class ParentAttribute : Attribute { } 

How do I write this?

Answer 1

Use Type.GetProperties() and PropertyInfo.GetValue()

    T GetPropertyValue<T>(object o)     {         T value = default(T);          foreach (System.Reflection.PropertyInfo prop in o.GetType().GetProperties())         {             object[] attrs = prop.GetCustomAttributes(typeof(ParentAttribute), false);             if (attrs.Length > 0)             {                 value = (T)prop.GetValue(o, null);                 break;             }         }          return value;     }