Is there a general way to detect if a property's type is an enumerable type?

Question

Given this:

class InvoiceHeader {     public int InvoiceHeaderId { get; set; }     IList<InvoiceDetail> LineItems { get; set; } } 

I'm currently using this code to detect if a class has a collection property:

void DetectCollection(object modelSource) {            Type modelSourceType = modelSource.GetType();     foreach (PropertyInfo p in modelSourceType.GetProperties())     {         if (p.PropertyType.IsGenericType &&  p.PropertyType.GetGenericTypeDefinition() == typeof(IList<>))         {             System.Windows.Forms.MessageBox.Show(p.Name);         }     } } 

Is there a general way to detect if the LineItems is an enumerable type? Some will use other enumerable type (e.g. ICollection), not an IList.

Answer 1

Your code doesn't actually check if the properties are Enumerable types but if they are generic IList's. Try this:

if(typeof(IEnumerable).IsAssignableFrom(p.PropertyType)) {    System.Windows.Forms.MessageBox.Show(p.Name); } 

Or this

if (p.PropertyType.GetInterfaces().Contains(typeof(IEnumerable))) {     System.Windows.Forms.MessageBox.Show(p.Name); }