It’s very simple really:

1. Create a new Class file (if you’re not using a multi-layered system, in your project’s Models folder) let’s called MyMembershipProvider.cs

2. Inherit that class from System.Web.Security.MembershipProvider

3. automatically create the needed methods (period + space in the inherit class)

Done!

All methods will have the NotImplementedException exception, all you need to do is edit each one and put your own code. For example, I define the GetUser as shown below:

public override MembershipUser GetUser(string username, bool userIsOnline)
{
    return db.GetUser(username);
}

dbis my Database Repository that I added into the class as

MyServicesRepository db = new MyServicesRepository();

there, you will find the GetUser method as:

public MembershipUser GetUser(string username)
{
    OS_Users user = this.FindUserByUsername(username);

    if (user == null)
        return
        new MembershipUser(
            providerName: "MyMembershipProvider",
            name: "",
            providerUserKey: null,
            email: "",
            passwordQuestion: "",
            comment: "",
            isApproved: false,
            isLockedOut: true,
            creationDate: DateTime.UtcNow,
            lastLoginDate: DateTime.UtcNow,
            lastActivityDate: DateTime.UtcNow,
            lastPasswordChangedDate: DateTime.UtcNow,
            lastLockoutDate: DateTime.UtcNow);

    return
        new MembershipUser(
            providerName: "MyMembershipProvider",
            name: user.username,
            providerUserKey: null,
            email: user.email,
            passwordQuestion: "",
            comment: "ANYTHING you would like to pass",
            isApproved: true,
            isLockedOut: user.lockout,
            creationDate: user.create_date,
            lastLoginDate: user.lastLoginDate,
            lastActivityDate: user.lastActivityDate,
            lastPasswordChangedDate: user.lastPasswordChangedDate,
            lastLockoutDate: user.lastLockoutDate);
}

Do this for all the methods you use (debug the project and see which ones you need) – I only use some, not all as I don’t really care about methods like ChangePasswordQuestionAndAnswer, DeleteUser, etc

just make sure that in your web.config you add the new Membership as:

<membership defaultProvider="MyMembershipProvider">
  <providers>
    <clear/>
    <add name="MyMembershipProvider" type="Your.NameSpace.MyMembershipProvider" connectionStringName="OnlineServicesEntities"
         enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false"
         maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10"
         applicationName="https://stackoverflow.com/" />
  </providers>
</membership>

You have a nice Video Tutorial from Chris Pels (dated 2007 but still mostly valid) and code for this as well, though Video Tutorial is in VB, but let’s you understand the steps…

http://www.asp.net/general/videos/how-do-i-create-a-custom-membership-provider

I did not only create my own Membership Provider but I created my Roles Provider as well, witch as you can see from above code, is as simple as the MemberShip and let’s you, in your application use things like:

[Authorize(Roles = "Partner, Admin")]
public ActionResult MyAction()
{

}

and

@if (Roles.IsUserInRole(Context.User.Identity.Name, "Admin"))
{
    <div>You're an ADMIN, Congrats!</div>
}

What is automagically create the needed methods (period + space in the inherit class)

You can either right-click, or have the cursor on the name and press Control + . and then space.