Can you extend HttpContext.Current.User.Identity p

问题:

Is there a way to override HttpContext.Current.User.Identity to add another property (screen name)?

My application uses Identity and I've left the unique identity as email. I store user data such as first / last name in a separate "Profile" table. Is there a way to store this information somewhere within HttpContext.Current?

It doesn't necessarily need to be within User. I have had a search and noticed there's a HttpContext.Current.ProfileBase. Not sure how to use it though - and I really don't want all the excess stuff that base comes with.

回答1:

If you are using Asp.Net Identity, then this is very easy to do with claims.

In your SignInAsync method (or, wherever you are creating the claims identity), add the GivenName and Surname claim types:

private async Task SignInAsync(ApplicationUser user, bool isPersistent)
{
    AuthenticationManager.SignOut(DefaultAuthenticationTypes.ExternalCookie);

    var identity = await UserManager.CreateIdentityAsync(user, DefaultAuthenticationTypes.ApplicationCookie);

    // Add the users primary identity details to the set of claims.
    var your_profile = GetFromYourProfileTable();

    identity.AddClaim(new Claim(ClaimTypes.GivenName, your_profile == null ? string.Empty : your_profile.FirstName));
    identity.AddClaim(new Claim(ClaimTypes.Surname, your_profile == null ? string.Empty : your_profile.LastName));

    AuthenticationManager.SignIn(new AuthenticationProperties() { IsPersistent = isPersistent }, identity);
}

You then use an extension method to IIdentity to pull the information out of the claims identity:

public static ProfileName GetIdentityName(this IIdentity identity)
{
    if (identity == null)
        return null;

    var first = (identity as ClaimsIdentity).FirstOrNull(ClaimTypes.GivenName),
    var last = (identity as ClaimsIdentity).FirstOrNull(ClaimTypes.Surname)

    return string.Format("{0} {1}", first, last).Trim();
}

internal static string FirstOrNull(this ClaimsIdentity identity, string claimType)
{
    var val = identity.FindFirst(claimType);

    return val == null ? null : val.Value;
}

Then, in your application (in your controller or view), you can just do:

var name = User.Identity.GetIdentityName();

回答2:

You can put value in HttpContext.Current.Items. It is dictionary which lifetime is single request.

You can use it like this:

public static string CurrentScreenName
{
    get
    {
        string screenName = (string)HttpContext.Current.Items["CurrentScreenName"];

        if (string.NullOrEmpty(screenName))
        {
             screenName = ResolveScreenName();
             HttpContext.Current.Items["CurrentScreenName"] = screenName;
        }
        return screenName;
    }
}

It will execute ResolveScreenName() only once for single request.

Also you can make extension method to access screen name from IIdentity

public static class Extensions
{
    public static string GetScreenName(this IIdentity identity)
    {
        return CurrentScreenName;
    }
}

And then use it like this:

string screenName = HttpContext.Current.User.Identity.GetScreenName();

回答3:

I found one implementation:

var profile = db.UserProfile.Where(u => u.UserId == user.Id).FirstOrDefault();
ProfileBase httpProfile = ProfileBase.Create(user.UserName);
httpProfile.SetPropertyValue("FullName", profile.FullName);
httpProfile.SetPropertyValue("FirstName", profile.FirstName);
httpProfile.SetPropertyValue("LastName", profile.LastName);

Then to get later...

ProfileBase userProfile = ProfileBase.Create(HttpContext.User.Identity.Name);
var fullName = userProfile.GetPropertyValue("FullName"));

回答4:

Absolutely! You need to create your own type that implements from IPrincipal, and take over security yourself. You can authenticate the user in an OWIN step, manually setting context.Request.User.