using System; using System.Configuration.Provider; namespace SPSolutions.Net.Mail { public sealed class MailBodyProviderCollection : ProviderCollection { public new MailBodyProvider this[string name] { get { return (MailBodyProvider)base[name]; } } public override void Add(ProviderBase provider) { if (provider == null) { throw new ArgumentNullException("provider"); } if (!(provider is MailBodyProvider)) { throw new ArgumentException("Provider_must_implement_type", "provider"); } base.Add(provider); } } }