如何在代码隐藏文件中生成AntiForgeryToken？

I have an action that resets a user's password. In that same action after the password is reset I want to login the user. I wanted to just use a "RedirectToAction" and send the username and password to my SignIn action. Since I have logic in that action that handles errors and what not. I have an action that resets a user's password.