[Solved] calculate the sum about Hashtable C# [closed]

Question

Given your comments, it sounds like you want the total count of items in each element of the ArrayList. You can use LINQ for this, although you’ll have to cast each element to a type since you aren’t using the preferred List<T> type.

return Allfile.Cast<Hashtable>().Sum(c => c.Count);

You should, however, as I commented, switch from ArrayList to List<T>, and from Hashtable to Dictionary<TKey, TValue>. These types improve everything about your code, particularly in readability and reliability. You would also not need the Cast function if you changed to a strongly-typed class, like List<T>.

On the other hand, if you’re just looking for the count of Hashtables, you can simply inspect the ArrayList.Count property:

return Allfile.Count;

Accepted Answer

Given your comments, it sounds like you want the total count of items in each element of the ArrayList. You can use LINQ for this, although you’ll have to cast each element to a type since you aren’t using the preferred List<T> type.

return Allfile.Cast<Hashtable>().Sum(c => c.Count);

You should, however, as I commented, switch from ArrayList to List<T>, and from Hashtable to Dictionary<TKey, TValue>. These types improve everything about your code, particularly in readability and reliability. You would also not need the Cast function if you changed to a strongly-typed class, like List<T>.

On the other hand, if you’re just looking for the count of Hashtables, you can simply inspect the ArrayList.Count property:

return Allfile.Count;