Programmatically adding a Membership Provider

Question

I have a .Net application that uses an arbitrary number of Membership providers. I will not go into the reasons, but I do not want these to be pre-configured, but I want to create and add them programmatically. Is there anyway to do this? I have no problem creating the providers, but Membership.Providers is readonly, so I can't add them.

Answer 1

An easy hack is to create a custom membership provider (as wrapper) first and hook it in web.config. Then you implement this provider to be able to authenticate users against a list of real membership providers.

As the wrapper is owned by you, you are only limited by your imagination.

Answer 2

Late, late answer, but you can use reflection:

public static class ProviderUtil
{
    static private FieldInfo providerCollectionReadOnlyField;

    static ProviderUtil()
    {
        Type t = typeof(ProviderCollection);
        providerCollectionReadOnlyField = t.GetField("_ReadOnly", BindingFlags.Instance | BindingFlags.NonPublic);
    }

    static public void AddTo(this ProviderBase provider, ProviderCollection pc)
    {
        bool prevValue = (bool)providerCollectionReadOnlyField.GetValue(pc);
        if (prevValue)
            providerCollectionReadOnlyField.SetValue(pc, false);

        pc.Add(provider);

        if (prevValue)
            providerCollectionReadOnlyField.SetValue(pc, true);
    }
}

Then, in your code, you can do something like this:

MyMembershipProvider provider = new MyMembershipProvider();
NameValueCollection config = new NameValueCollection();
// Configure your provider here.  For example,
config["username"] = "myUsername";
config["password"] = "myPassword";
provider.Initialize("MyProvider", config); 

// Add your provider to the membership provider list
provider.AddTo(Membership.Providers);

It's a hack, because we're using reflection to set the "_ReadOnly" private field, but it seems to work.

Here's a great post about this issue: http://elegantcode.com/2008/04/17/testing-a-membership-provider/

Another good post: http://www.endswithsaurus.com/2010/03/inserting-membershipprovider-into.html

Pay special attention to the warnings of using _ReadOnly in those posts, as you'll want to weigh the downsides of manipulating a readonly collection vs. your project requirements and what you're trying to accomplish.

Regards,

-Doug