dbml 连接

    public class WorkflowDataService
    {
        private const string WORKFLOW_ACTION_CONNECTION_STRING = "WorkflowActionConnection";

        internal static WorkflowActionDataContext NewActionDataContext()
        {
            return NewActionDataContext(null);
        }

        internal static WorkflowActionDataContext NewActionDataContext(IDbConnection connection)
        {
            return NewActionDataContext(connection, true);
        }
        /// <summary>
        /// Gets the new database.
        /// </summary>
        /// <param name="objectTrackingEnabled">if set to <c>true</c> [object tracking enabled].</param>
        /// <returns></returns>
        internal static WorkflowActionDataContext NewActionDataContext(IDbConnection connection, bool objectTrackingEnabled)
        {
            WorkflowActionDataContext context = null;

            if (connection == null)
            {
                context = new WorkflowActionDataContext(
                    ConfigurationManager.ConnectionStrings[WORKFLOW_ACTION_CONNECTION_STRING].ConnectionString
                    );
            }
            else
            {
                context = new WorkflowActionDataContext(connection);
            }

            if (null == context)
            {
                throw new DataContextException { DataContextType = typeof(WorkflowActionDataContext) };
            }
            else
            {
                context.ObjectTrackingEnabled = objectTrackingEnabled;
            }
            return context;
        }
    }