Helper to make using DbProviderFactories.GetFactory() easier to use with dynamic provider loading (no app.config required)

DbProviderHelper.cs

class DbProviderHelper
{
    const string AssemblyQualifiedName = "AssemblyQualifiedName";
    const string Name = "Name";
    const string InvariantName = "InvariantName";
    const string Description = "Description";

    internal class FactoryInfo
    {
        public string InvariantName { get; set; }
        public string AssemblyQualifiedName { get; set; }
        public string Name { get; set; }
        public string Description { get; set; }
    }

    public List<FactoryInfo> Factories { get; set; }
    public string DbProvider { get; set; }
    public string ConnectionString { get; set; }

    DbProviderFactory m_factory;

    public DbProviderHelper()
    {
        Factories = new List<FactoryInfo>();

        var factories = DbProviderFactories.GetFactoryClasses();
        foreach (DataRow dataRow in factories.Rows) {
            var info = new FactoryInfo {
                InvariantName = dataRow [InvariantName] as string,
                Name = dataRow [Name] as string,
                AssemblyQualifiedName = dataRow [AssemblyQualifiedName] as string,
                Description = dataRow [Description] as string
            };

            Factories.Add(info);
        }
    }

    public bool InvariantNamePresentInFactories(string invariantName)
    {
        return Factories.Count(f => f.InvariantName == invariantName) > 0;
    }

    public DbConnection CreateConnection()
    {
        if (DbProvider == null)
            throw new ApplicationException("No DbProvider dude!");

        if (ConnectionString == null)
            throw new ApplicationException("No ConnectionString dude!");

        if (m_factory == null) 
        {
            if (InvariantNamePresentInFactories(DbProvider)) 
            {
                // Look up factory via InvariantName
                m_factory = DbProviderFactories.GetFactory(DbProvider);
            } 
            else 
            {
                // Look up factory via QualifiedAssemblyName (in a DataRow)
                var table = new DataTable();
                var column = new DataColumn();
                column.DataType = Type.GetType("System.String");
                column.ColumnName = AssemblyQualifiedName;
                table.Columns.Add(column);
                var row = table.NewRow();
                row [AssemblyQualifiedName] = DbProvider;

                m_factory = DbProviderFactories.GetFactory(row);
            }
        }

        var connection = m_factory.CreateConnection();
        connection.ConnectionString = ConnectionString;
        connection.Open();

        return connection;
    }
}