http://wiki.yetanotherforum.net/AspNetMembershipIntegration.ashx ) but i got error when i used the following code as below

Compiler Error Message: CS0103: The name 'yaf' does not exist in the current context

Source Error:

System.Web.UI.WebControls.Login loginControl = (System.Web.UI.WebControls.Login)sender;

String password = FormsAuthentication.HashPasswordForStoringInConfigFile(loginControl.Password, "md5");

Object userID = yaf.DB.user_login(1, loginControl.UserName, password);

if (userID == DBNull.Value)

May I know how to solve this problem? Thanks.