How to read assembly attributes

Ok, perhaps a bit out of date now for the original question but I will present this for future reference anyway.

If you want to do it from inside the assembly itself then use the following :

using System.Runtime.InteropServices;
using System.Reflection;

object[] customAttributes = this.GetType().Assembly.GetCustomAttributes(false);

You can then iterate through all of the custom attributes to find the one(s) you require e.g.

foreach (object attribute in customAttributes)
{
  string assemblyGuid = string.Empty;    

  if (attribute.GetType() == typeof(GuidAttribute))
  {
    assemblyGuid = ((GuidAttribute) attribute).Value;
    break;
  }
}

I've created this extension method that uses Linq:

public static T GetAssemblyAttribute<T>(this System.Reflection.Assembly ass) where T :  Attribute
{
    object[] attributes = ass.GetCustomAttributes(typeof(T), false);
    if (attributes == null || attributes.Length == 0)
        return null;
    return attributes.OfType<T>().SingleOrDefault();
}

and then you can conveniently use it like that:

var attr = targetAssembly.GetAssemblyAttribute<AssemblyDescriptionAttribute>();
if(attr != null)
     Console.WriteLine("{0} Assembly Description:{1}", Environment.NewLine, attr.Description);

This is reasonably easy. You have to use reflection. You need an instance of Assembly that represents the assembly with the attributes you want to read. An easy way of getting this is to do:

typeof(MyTypeInAssembly).Assembly

Then you can do this, for example:

object[] attributes = assembly.GetCustomAttributes(typeof(AssemblyProductAttribute), false);

AssemblyProductAttribute attribute = null;
if (attributes.Length > 0)
{
   attribute = attributes[0] as AssemblyProductAttribute;
}

Referencing attribute.Product will now give you the value you passed to the attribute in your AssemblyInfo.cs. Of course, if the attribute you look for can occur more than once, you may get multiple instances in the array returned by GetCustomAttributes, but this is not usually an issue for assembly level attributes like the ones you hope to retrieve.