'property' : Named attribute argument can't be a read only property
A property that is valid for an attribute was used as an argument to the attribute, which is not allowed.
The following sample, which uses the obsolete attribute, generates CS0632:
using System; [obsolete("Obsolescence message",IsError=false)] // CS0632 // the following line shows how to pass an argument to this property // [obsolete("Obsolescence message",false)] interface I1 { } public class CI1 : I1 { } public class MainClass { public static void Main () { object[] attrs = typeof(I1).GetCustomAttributes(); // the next line shows how this read-only property might be used Console.WriteLine (((ObsoleteAttribute)attrs[0]).IsError); } }