How to set the current user for WebPartManager?

Question

From what I've been reading, the following code should first ensure that a MembershipUser record exists for "ArthurDent", then set "ArthurDent" as the current user, and finally assign his MembershipUser record to the variable mUser.

if (Membership.GetUser("ArthurDent") == null)
{
   Membership.CreateUser("ArthurDent", "thisisapassword");
}
FormsAuthentication.SetAuthCookie("ArthurDent", true);
MembershipUser mUser = Membership.GetUser();

Instead, the variable mUser remains null.'

My goal is to programmatically set the current user to a valid record so that I can set a WebPartManager.DisplayMode on a page that started erroring out when I added BlogEngine to my web site.

Answer 1

The answer is that BlogEngine actively suppresses the normal workings of Page.User.Identity, which Membership.GetUser() retrieves. When I replaced FormsAuthentication.SetAuthCookie with the following code from BlogEngine...

Security.AuthenticateUser("ArthurDent", "thisisapassword", true);

... it authenticated Arthur and logged him in.

Answer 2

This problem generally occurs when the application breaks a rule defined in the web.config file. For instance I ran your code in my local environment using Windows Authentication and CreateUser at first failed because the password string was of insufficient length. I padded the password with additional characters and was able to create user with the supplied code. Check the section to examine password prerequisites. Upon first examination this looks like a configuration problem.