确定匿名类型的属性是否为泛型集合

Question

I need a method to cycle through each object's properties and log the property name and value. On occasion, however, I hit a property that is a list object and the whole thing crashes. I've gather the condition below from various SO posts but it returns false every time. Wondering how to test if your method property is a generic collection type?

Class Definition

public class DtccProducer
{
    public string ProducerDateOfBirth { get; set; }
    public string ProducerGender { get; set; }
    public string TransactionType { get; set; }
    public List<BigAddress> Addresses { get; set; }
    public List<BigCommunicationItem> Communications { get; set; }
}

Method

    private static void ParseProducer(object obj)
    {
        StringBuilder s = new StringBuilder();
        Type objType = obj.GetType();

        foreach (PropertyInfo info in objType.GetProperties())
        {
            string key = info.Name;

            Type propType = info.PropertyType;

            if (propType.IsGenericType && typeof(ICollection<>).IsAssignableFrom(propType.GetGenericTypeDefinition()))
            {
                // This condition never passes - always evaluates to false
            }
            else
            {
                string value = (string) info.GetValue(obj, null);
                _sb.AppendLine(key + ": " + value);                    
            }
        }
    }

Answer 1

This is the code I use to identify lists in my log:

if (!propType.IsPrimitive && !propType.IsEnum && propType != typeof(string) && propType.GetInterfaces().Any(x => x.IsGenericType 
           && x.GetGenericTypeDefinition() == typeof(IEnumerable<>)))

Edit: I've added some additional checks to filter out primitive types (int's, bool's, etc.), enum's and strings.