LINQ with ArrayLists

LINQ with ArrayLists

• TimirP

  Starting with .NET 2.0, it's probably better to use a generic List instead of ArrayList. System.Collections.Generic.List<> works the same way as ArrayList, is type safe, performs better in most cases (especially when the list items are value types) .
  
  
  

• ChrisMM.

  ArrayLists can easily be queried with LINQ, but you must manually supply the missing element type using the Cast<T>() method. For example, to query an ArrayList containing Customer objects you would write

  var q =
  from c in arrayList.Cast<Customer>()
  where c.State == "WA"
  select { c.Name, c.Phone };

  The final version of C# 3.0 will allow you to specify the element type in the from clause of the query, but this isn't supported in the May 2006 CTP:

  var q =
  from Customer c in arrayList
  where c.State == "WA"
  select { c.Name, c.Phone };

  This will simply get translated into a call to Cast<T>() with the given type.

  Anders

  
  
• LINQ with ArrayLists