Could "Context.User" be a null? - asp.net

In my MasterPage code-behind I try to get UserID of the authenticated (if it has) one:
public Guid CurrentUserID
{
get
{
Guid userID = new Guid();
if (Context.User.Identity.IsAuthenticated)
{
MembershipUser user = Membership.GetUser(Context.User.Identity.Name);
userID = (Guid)user.ProviderUserKey;
}
return userID;
}
}
Once the error "Object reference not set to an instance of an object" appeared. I suspect the problem is in the case Context.User=null. Could it be the reason?

Maybe the user was deleted by the db while he was authenticated, so Membership.GetUser returned null and user.ProviderUserKey has thrown NullReferenceException.

Related

MVC5 ApplicationUser custom properties

I am trying to get to grips with the new Membership system introduced in ASP.NET MVC 5 and I've come across a small issue which I am pretty sure you will be able to help me with.
I am going based off this tutorial and have introduced custom properties to ApplicationUser such as Name, Surname, DOB, etc.
However, instead of creating the user, I am trying to update the currently logged in one. I am looking at the controller method which is currently used to change password.
public async Task<ActionResult> Manage(ManageUserViewModel model)
{
string userId = User.Identity.GetUserId();
bool hasLocalLogin = await IdentityManager.Logins.HasLocalLoginAsync(userId);
ViewBag.HasLocalPassword = hasLocalLogin;
ViewBag.ReturnUrl = Url.Action("Manage");
if (hasLocalLogin)
{
if (ModelState.IsValid)
{
IdentityResult result = await IdentityManager.Passwords.ChangePasswordAsync(User.Identity.GetUserName(), model.OldPassword, model.NewPassword);
if (result.Success)
{
return RedirectToAction("Manage", new { Message = "Your password has been changed." });
}
else
{
AddErrors(result);
}
}
}
else
{
// User does not have a local password so remove any validation errors caused by a missing OldPassword field
ModelState state = ModelState["OldPassword"];
if (state != null)
{
state.Errors.Clear();
}
if (ModelState.IsValid)
{
// Create the local login info and link it to the user
IdentityResult result = await IdentityManager.Logins.AddLocalLoginAsync(userId, User.Identity.GetUserName(), model.NewPassword);
if (result.Success)
{
return RedirectToAction("Manage", new { Message = "Your password has been set." });
}
else
{
AddErrors(result);
}
}
}
// If we got this far, something failed, redisplay form
return View(model);
}
How exactly would I go on about updating an ApplicationUser's Surname for example? Do I need to call the DbContext or?
I hope my question is clear.
Explore IdentityManager.Store.UserManagement and IdentityManager.Store.Users.
ApplicationUser cUser = (ApplicationUser) await IdentityManager.Store.Users.FindByNameAsync(HttpContext.User.Identity.Name, new System.Threading.CancellationToken());
cUser.Surname = "New Something";
IdentityResult result1 = await IdentityManager.Store.SaveChangesAsync();
Above code is an example only. Basically you need to explore the Store property of IdentityManage.
When we used the Users object of our database context we ran into other tracking errors. In our application, we would retrieve users as such
var user = UserManager.FindById(userId);
Edit the properties:
user.StorageName = "gooblygook";
//whatever other properties you would like to use
And then we would save it with the UserManager in the controller:
UserManager.Update(user);
This is currently a working solution for us.
Mark the Person object as virtual in your ApplicationUser definition. That worked for me.
public class ApplicationUser : IdentityUser
{
public virtual Person Person { get; set; }

umbraco membership createuser & select profile data

I have created a class to handle membership user creation with custom fields.
I have done it based on this solutions:
How to assign Profile values?
Using ASP .NET Membership and Profile with MVC, how can I create a user and set it to HttpContext.Current.User?
namespace CCL
{
public static MemberProfile CurrentUser
{
get
{
if (Membership.GetUser() != null)
return ProfileBase.Create(Membership.GetUser().UserName) as MemberProfile;
else
return null;
}
}
}
And now I'm trying to use create the user and get the profile data:
if (Membership.GetUserNameByEmail(email) == null)
{
MembershipUser member = Membership.CreateUser(username, password, email);
Roles.AddUserToRole(username, "WebsiteUsers");
CCL.MemberProfile currentProfile = CCL.MemberProfile.CurrentUser;
bool exists = currentProfile != null;
Response.Write(exists.ToString());
}
but currentProfile is returning null.
So I'm unable to assign values from the form to my member custom properties which are handled by the properties set in the class :(
I don't get how I can make it working :(
Does anyone have some thoughts? Thanks
Suggestion 1:
Make sure that ProfileBase.Create returns something that can be cast to a "MemberProfile", otherwise if it can't then casting it will just return NULL.
Suggestion 2:
Make sure the context you are running in has a logged in user, so your call to Membership.GetUser() can find the current user object.
Other thoughts:
The ProfileBase.Create method assumes that the username you pass in is an authenticated user, I'm not sure on it's behavior when the user isn't authenticated..maybe it returns NULL?

How to I add more custom fields using custom membership in mvc?

I have overridden the membership methods to create a custom membership.
In the account model I've overridden the method CreateUser:
public override MembershipUser CreateUser(string username, string password,
string email, string passwordQuestion, string passwordAnswer,
bool isApproved, object providerUserKey, out MembershipCreateStatus status)
{
ValidatePasswordEventArgs args = new ValidatePasswordEventArgs(
username, password, true);
OnValidatingPassword(args);
if (args.Cancel)
{
status = MembershipCreateStatus.InvalidPassword;
return null;
}
if (RequiresUniqueEmail && GetUserNameByEmail(email) != "")
{
status = MembershipCreateStatus.DuplicateEmail;
return null;
}
MembershipUser u = GetUser(username, false);
if (u == null)
{
UserRepository _user = new UserRepository();
// Here I call my new method which has fields I've created in the
// User table; I'm using entity framework.
_user.CreateUser(username, password, email);
status = MembershipCreateStatus.Success;
return GetUser(username, false);
}
else
{
status = MembershipCreateStatus.DuplicateUserName;
}
return null;
}
public MembershipUser CreateUser(string username, string password,
string email)
{
using (CustomMembershipDB db = new CustomMembershipDB())
{
User user = new User();
user.UserName = username;
user.Email = email;
user.PasswordSalt = CreateSalt();
user.Password = CreatePasswordHash(password, user.PasswordSalt);
user.CreatedDate = DateTime.Now;
user.IsActivated = false;
user.IsLockedOut = false;
user.LastLockedOutDate = DateTime.Now;
user.LastLoginDate = DateTime.Now;
//Generate an email key
// user.NewEmailKey = GenerateKey();
db.AddToUsers(user);
db.SaveChanges();
//send mail
// SendMail(user);
return GetUser(username);
}
}
Now here I need to add more two fields like first name and last name but how can I pass it to the above method?
As the override method CreateUser will give me an error if I add parameters like firstname and last name into it :(
You need to implement Custom Membership User. Here is a sample implementation:
http://msdn.microsoft.com/en-us/library/ms366730.aspx
Also take a look at this thread:
Implement Custom MembershipUser and Custom MembershipProvider
Implementing Custom MembershipUser
You can leave the AspNetUsers table intact, and create a new table to store the extra information (linked to the original one). This way you'll not break any existing code in the membership provider.
The original AspNetUsers table has:
[Id],[Email],[EmailConfirmed],[PasswordHash],[SecurityStamp],[PhoneNumber],[PhoneNumberConfirmed],[TwoFactorEnabled],[LockoutEndDateUtc],[LockoutEnabled],[AccessFailedCount],[UserName]
The new table to store extra data can have for example:
[Id],[UserId][DateOfBirth],[Biography], etc.
Where [UserId] is the foreign key to AspNetUsers table.
One advantage of this approach, is that you can create multiple types of users, each storing its related info in a different table, while common data is still in the original table.
How to:
First update the RegisterViewModel to contain the extra data you want.
Update the Register method in the Account Controller, here's the original method updated with the code to insert new profile data:
[HttpPost]
[AllowAnonymous]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Register(RegisterViewModel model)
{
if (ModelState.IsValid)
{
var user = new ApplicationUser() { UserName = model.Email, Email = model.Email };
IdentityResult result = await UserManager.CreateAsync(user, model.Password);
if (result.Succeeded)
{
// Start of new code ----------------------------------------
// Get Id of newly inserted user
int userId = user.Id; // Get Id of newly inserted user
// Create a profile referencing the userId
AddUserProfile(userId, model);
// End of new code ----------------------------------------
await SignInAsync(user, isPersistent: false);
return RedirectToAction("Index", "Home");
}
else
{
AddErrors(result);
}
}
return View(model);
}
Implement the AddUserProfile(int userId, RegisterViewModel model) method as you wish. You'll collect the extra data from the model object along with the userId and save the new profile object in the DB.
Make a class that inherits from MembershipProvider and implement methods that are identical by just calling the SqlMembershipProvider but change others that you want a different Functionality.
Take a look at this article SQLite 3.0 Membership and Role Provider for ASP.NET 2.0
UPDATE:
The Membership system in ASP.NET was designed to create a standardized
API for working with user accounts, a task faced by many web
applications (refer back to Part 1 of this article series for a more
in-depth look at Membership). While the Membership system encompasses
core user-related properties - username, password, email address, and
so on - oftentimes additional information needs to be captured for
each user. Unfortunately, this additional information can differ
wildly from application to application.
Rather than add additional user attributes to the Membership system,
Microsoft instead created the Profile system to handle additional user
properties. The Profile system allows the additional, user-specific
properties to be defined in the Web.config file and is responsible for
persisting these values to some data store.
Reference: Examining ASP.NET's Membership, Roles, and Profile - Part 6
This is how I have accomplished somthing like this. I added event onCreatedUser to CreateUserWizard and when you press CreateUser button it loads method
protected void CreateUserWizard1_CreatedUser(object sender, EventArgs e)
{
MembershipUser mu = Membership.GetUser(CreateUserWizard1.UserName);
int idOfInsertedUser = (int)mu.ProviderUserKey;
TextBox tb1 = (TextBox)CreateUserWizard1.CreateUserStep.ContentTemplateContainer.FindControl("FirstName";
string firstName= tb1.Text;
TextBox tb2 = (TextBox)CreateUserWizard1.CreateUserStep.ContentTemplateContainer.FindControl("LastName";
string lastName= tb2.Text;
// now you have values of two more fields, and it is time to call your Database methods for inserting them in tables of choice...
}

ASP.NET how to store user login data in the APP

Just wondering what the best way to store user login data on successful login in my application. I.e. when logged in at the moment I do something like this in my login script
Session("loggedIn") = "Yes"
Session("userName") = reader_login("useremail").ToString()
Session("userId") = reader_login("user_ID").ToString()
Session("firstName") = reader_login("firstName").ToString()
Session("lastName") = reader_login("lastName").ToString()
And then I use these session variables on my scripts, but just noticed that every time I want to use some of these session variables I do need to check if they are nut null before calling them, seems a bit clumsy to repeat these for a lot of my .aspx pages. Is there a better way to do this ?
EDIT :
Also I am wondering why do I need to add the IS NUll check for the session on each script I use session variables I put the check in the master page but noticed I still get null exception in my usercontrol which is referenced in my master page but does not have the IS null check
Session is not the way to check whether user is authenticated or not. Session may be cleared on demand by administrator when clearing app pool, or by the low memory on server. You won't wish to log out user in such cases. The builtin and reccommended way for doing this in ASP.NET is storing data in authentication cookie. Once the user is logged in, you issue the cookie that contains all the data, including user id, name, etc. And then, you don't have to check every property in session for null, more simple - you just check if the user is authenticated - then you've got the data, else -not. And the other benefit, if you substitute builtin principal with custom one, you can define strongly typed object that holds user data, no more casting from objects extracted from session. Here're the examples for defining custom principal with forms authentication
First, let's define custom MyIdentity and MyPrincipal
public class MyIdentity : IIdentity
{
private FormsAuthenticationTicket _Ticket;
private int _userId = 0;
public FormsAuthenticationTicket Ticket
{
get { return _Ticket; }
}
public string Name
{
get { return _Ticket.Name; }
}
public int UserId
{
get
{
if (_userId == 0)
_userId = Convert.ToInt32(_Ticket.UserData.Split("|".ToCharArray())[0]);
return _userId;
}
}
public Identity(FormsAuthenticationTicket ticket)
{
this._Ticket = ticket;
}
public string AuthenticationType
{
get { return "Custom"; }
}
public bool IsAuthenticated
{
get { return UserId > 0; }
}
}
Then the MyPrincipal that holds MyIdentity
public class MyPrincipal : IPrincipal
{
private MyIdentity _Identity;
public Principal(MyIdentity identity)
{
_Identity = identity;
}
public IIdentity Identity
{
get { return _Identity; }
}
public bool IsInRole(string role)
{
return false;
}
}
Then substitute original forms user with the custom one. In Global.asax
private void Application_OnPostAuthenticateRequest(object sender, EventArgs e)
{
IPrincipal usr = HttpContext.Current.User;
// If we are dealing with an authenticated forms authentication request
if (usr.Identity.IsAuthenticated && usr.Identity.AuthenticationType == "Forms")
{
FormsIdentity formsIdentity = usr.Identity as FormsIdentity;
// Create a CustomIdentity based on the FormsAuthenticationTicket
IIdentity identity = new MyIdentity(formsIdentity.Ticket);
IPrincipal principal = new MyPrincipal(identity);
// Attach the CustomPrincipal to HttpContext.User and Thread.CurrentPrincipal
HttpContext.Current.User = principal;
Thread.CurrentPrincipal = principal;
}
}
Define method for issuing forms authentication ticket. Later, the custom MyIdentity class will extract userId and other methods from userData.
public static HttpCookie GetAuthCookie(string userName, string userData, bool createPersistentCookie, HttpSessionStateBase session)
{
HttpCookie authCookie = FormsAuthentication.GetAuthCookie(userName, createPersistentCookie);
FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(authCookie.Value);
FormsAuthenticationTicket newTicket = new FormsAuthenticationTicket(ticket.Version, ticket.Name, ticket.IssueDate, ticket.Expiration, ticket.IsPersistent, userData, session.SessionID);
authCookie.Value = FormsAuthentication.Encrypt(newTicket);
return authCookie;
}
When the user is checked and is authenticated, return them authentication cookie
Response.Cookies.Add(AuthenticationCookie.GetAuthCookie(model.UserName, GetUserInfo(model.UserName, passwordHash), model.RememberMe, Session));
//GetUserInfo returns | separated string of user datas. "userId|userName|firstName|lastName" for example.
And at last, using all of the above in code
if(User.Identity.IsAuthenticated)
{
int userId = ((MyIdentity)User.Identity).UserId;
}
This may seem the larger code, but in runtime it'll give much more benefits than storing all the data in session. The main of them are null checking and casting every time.
You could load this through a single object which you put in the Session. This will remove all your strings as you can just set properties. Also you can check if the object is available in the session, if it's not the user is not logged in?
public class CurrentUserObject
{
public string UserName { get; set; }
public string UserID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public CurrentUserObject(string userName, string userID, string firstName, string lastName)
{
UserName = userName;
UserID = userID;
FirstName = firstName;
LastName = lastName;
}
}
You can instantiate this object and store it in Session("CurrentUser") or something. If you request this session variable and it turns out to be null, your user is not logged in. I would advise you to do this in a master page or something by the way to avoid duplication of this code.
you don't have to store "loggedIn" in session.
you can use Session["userName"] to check, if it is null, not logged in; not null, logged in.
try to use one session item to track user login status, such username or userid.
also you can encapsule the logic into a method such as
static bool CheckLogin(HttpSession sessionState, out username, out userId, out firstName, out LastName);
FYI
may be you need to use caching in your application because you are going to check if null or not every time i think for save use data caching will be better and here are some links :
http://msdn.microsoft.com/en-us/library/xsbfdd8c(v=vs.71).aspx
http://msdn.microsoft.com/en-us/library/ms972379.aspx
http://www.exforsys.com/tutorials/asp.net/caching-in-asp.net.html
http://www.codeproject.com/KB/web-cache/cachingaspnet.aspx
Hope it helps mark as answered if it helps :)

Is Roles.IsUserInRole behaving as expected in the following simple scenario?

In a custom role provider (inheriting from RoleProvider) in .NET 2.0, the IsUserInRole method has been hard-coded to always return true:
public override bool IsUserInRole(string username, string roleName) { return true; }
In an ASP.NET application configured to use this role provider, the following code returns true (as expected):
Roles.IsUserInRole("any username", "any rolename"); // results in true
However, the following code returns false:
Roles.IsUserInRole("any rolename"); // results in false
Note that User.IsInRole("any rolename") is also returning false.
Is this the expected behavior?
Is it incorrect to assume that the overload that only takes a role name would still be invoking the overridden IsUserInRole?
Update: Note that there doesn't seem to be an override available for the version that takes a single string, which has led to my assumption in #2.
I looked at Roles.IsUserInRole(string rolename) in .net reflector, and it resolves to the following:
public static bool IsUserInRole(string roleName)
{
return IsUserInRole(GetCurrentUserName(), roleName);
}
I would take a look at your current user. Here's why:
private static string GetCurrentUserName()
{
IPrincipal currentUser = GetCurrentUser();
if ((currentUser != null) && (currentUser.Identity != null))
{
return currentUser.Identity.Name;
}
return string.Empty;
}
I would be willing to bet this is returning an empty string because you either don't have a Current User, or its name is an empty string or null.
In the IsUserInRole(string username, string roleName) method, there is the following block of code right near the beginning:
if (username.Length < 1)
{
return false;
}
If your GetCurrentUserName() doesn't return anything meaningful, then it will return false before it calls your overridden method.
Moral to take away from this: Reflector is a great tool :)
Also beware if you have selected cacheRolesInCookie="true" in the RoleManager config. If you have added a new role to the database, it might be looking at the cached version in the cookie.
I had this problem and the solution was to delete the cookie and re-login.
This may help someone - be aware:
If you are using the login control to authenticate - the username entered into the control becomes the HttpContext.Current.User.Identity.Name which is used in the Roles.IsUserInRole(string rolename) and more specifically - the membership's GetUser() method. So if this is the case make sure you override the Authenticate event, validate the user in this method and set the username to a value that your custom membership provider can use.
protected void crtlLoginUserLogin_Authenticate(object sender, AuthenticateEventArgs e)
{
bool blnAuthenticate = false;
string strUserName = crtlLoginUserLogin.UserName;
if (IsValidEmail(strUserName))
{
//if more than one user has email address - must authenticate by username.
MembershipUserCollection users = Membership.FindUsersByEmail(strUserName);
if (users.Count > 1)
{
crtlLoginUserLogin.FailureText = "We are unable to determine which account is registered to that email address. Please enter your Username to login.";
}
else
{
strUserName = Membership.GetUserNameByEmail(strUserName);
blnAuthenticate = Membership.ValidateUser(strUserName, crtlLoginUserLogin.Password);
//setting the userLogin to the correct user name (only on successful authentication)
if (blnAuthenticate)
{
crtlLoginUserLogin.UserName = strUserName;
}
}
}
else
{
blnAuthenticate = Membership.ValidateUser(strUserName, crtlLoginUserLogin.Password);
}
e.Authenticated = blnAuthenticate;
}

Resources