Template implementation of a custom ASP.NET RoleProvider, using C#

CustomRoleProvider.cs

using System;
using System.Collections.Specialized;
using System.Configuration.Provider;
using System.Linq;
using System.Web.Configuration;
using System.Web.Security;

namespace Custom.Providers
{
    public class CustomRoleProvider : RoleProvider
    {
        private string _applicationName;
        private string _connectionString;


        /// <summary>
        /// Gets or sets the name of the application to store and retrieve role information for.
        /// </summary>
        /// <returns>The name of the application to store and retrieve role information for.</returns>
        public override string ApplicationName
        {
            get
            {
                return _applicationName;
            }
            set
            {
                _applicationName = value;
            }
        }

        /// <summary>
        /// [Not Implemented] Adds the specified user names to the specified roles for the configured applicationName.
        /// </summary>
        /// <param name="usernames">A string array of user names to be added to the specified roles.</param>
        /// <param name="roleNames">A string array of the role names to add the specified user names to.</param>
        /// <exception cref="NotImplementedException">This method has not been implemented, and will throw a <c>NotImplementedException</c> exception when called.</exception>
        public override void AddUsersToRoles( string[] usernames, string[] roleNames )
        {
            throw new NotImplementedException();
        }


        /// <summary>
        /// [Not Implemented] Adds a new role to the data source for the configured applicationName.
        /// </summary>
        /// <param name="roleName">The name of the role to create.</param>
        /// <exception cref="NotImplementedException">This method has not been implemented, and will throw a <c>NotImplementedException</c> exception when called.</exception>
        public override void CreateRole( string roleName )
        {
            throw new NotImplementedException();
        }


        /// <summary>
        /// [Not Implemented] Removes a role from the data source for the configured applicationName.
        /// </summary>
        /// <param name="roleName">The name of the role to delete.</param>
        /// <param name="throwOnPopulatedRole">If true, throw an exception if <paramref name="roleName"/> has one or more members and do not delete <paramref name="roleName"/>.</param>
        /// <returns>
        /// true if the role was successfully deleted; otherwise, false.
        /// </returns>
        /// <exception cref="NotImplementedException">This method has not been implemented, and will throw a <c>NotImplementedException</c> exception when called.</exception>
        public override bool DeleteRole( string roleName, bool throwOnPopulatedRole )
        {
            throw new NotImplementedException();
        }


        /// <summary>
        /// [Not Implemented] Gets an array of user names in a role where the user name contains the specified user name to match.
        /// </summary>
        /// <param name="roleName">The role to search in.</param>
        /// <param name="usernameToMatch">The user name to search for.</param>
        /// <returns>
        /// A string array containing the names of all the users where the user name matches <paramref name="usernameToMatch"/> and the user is a member of the specified role.
        /// </returns>
        /// <exception cref="NotImplementedException">This method has not been implemented, and will throw a <c>NotImplementedException</c> exception when called.</exception>
        public override string[] FindUsersInRole( string roleName, string usernameToMatch )
        {
            throw new NotImplementedException();
        }


        /// <summary>
        /// Gets a list of all the roles for the configured applicationName.
        /// </summary>
        /// <returns>
        /// A string array containing the names of all the roles stored in the data source for the configured applicationName.
        /// </returns>
        public override string[] GetAllRoles()
        {
            throw new NotImplementedException(); // NOTE: this needs to be implemented
        }


        /// <summary>
        /// Gets a list of the roles that a specified user is in for the configured applicationName.
        /// </summary>
        /// <param name="username">The user to return a list of roles for.</param>
        /// <returns>
        /// A string array containing the names of all the roles that the specified user is in for the configured applicationName.
        /// </returns>
        public override string[] GetRolesForUser( string username )
        {
            throw new NotImplementedException(); // NOTE: this needs to be implemented
        }


        /// <summary>
        /// Gets a list of users in the specified role for the configured applicationName.
        /// </summary>
        /// <param name="roleName">The name of the role to get the list of users for.</param>
        /// <returns>
        /// A string array containing the names of all the users who are members of the specified role for the configured applicationName.
        /// </returns>
        public override string[] GetUsersInRole( string roleName )
        {
            throw new NotImplementedException(); // NOTE: this needs to be implemented
        }


        /// <summary>
        /// Gets a value indicating whether the specified user is in the specified role for the configured applicationName.
        /// </summary>
        /// <param name="username">The user name to search for.</param>
        /// <param name="roleName">The role to search in.</param>
        /// <returns>
        /// true if the specified user is in the specified role for the configured applicationName; otherwise, false.
        /// </returns>
        public override bool IsUserInRole( string username, string roleName )
        {
            throw new NotImplementedException(); // NOTE: this needs to be implemented
        }


        /// <summary>
        /// [Not Implemented] Removes the specified user names from the specified roles for the configured applicationName.
        /// </summary>
        /// <param name="usernames">A string array of user names to be removed from the specified roles.</param>
        /// <param name="roleNames">A string array of role names to remove the specified user names from.</param>
        /// <exception cref="NotImplementedException">This method has not been implemented, and will throw a <c>NotImplementedException</c> exception when called.</exception>
        public override void RemoveUsersFromRoles( string[] usernames, string[] roleNames )
        {
            throw new NotImplementedException();
        }


        /// <summary>
        /// Gets a value indicating whether the specified role name already exists in the role data source for the configured applicationName.
        /// </summary>
        /// <param name="roleName">The name of the role to search for in the data source.</param>
        /// <returns>
        /// true if the role name already exists in the data source for the configured applicationName; otherwise, false.
        /// </returns>
        public override bool RoleExists( string roleName )
        {
            throw new NotImplementedException(); // NOTE: this needs to be implemented
        }


        #region Initialization


        /// <summary>
        /// Initializes the provider.
        /// </summary>
        /// <param name="name">The friendly name of the provider.</param>
        /// <param name="config">A collection of the name/value pairs representing the provider-specific attributes specified in the configuration for this provider.</param>
        /// <exception cref="T:System.ArgumentNullException">The name of the provider is null.</exception>
        ///   
        /// <exception cref="T:System.ArgumentException">The name of the provider has a length of zero.</exception>
        ///   
        /// <exception cref="T:System.InvalidOperationException">An attempt is made to call <see cref="M:System.Configuration.Provider.ProviderBase.Initialize(System.String,System.Collections.Specialized.NameValueCollection)"/> on a provider after the provider has already been initialized.</exception>
        public override void Initialize(string name, NameValueCollection config)
        {
            if (config == null)
            {
                throw new ArgumentNullException("config");
            }

            if (name == null || name.Length == 0)
            {
                name = "CustomRoleProvider";
            }

            if (String.IsNullOrEmpty(config["description"]))
            {
                config.Remove("description");
                config.Add("description", "Custom RoleProvider");
            }

            // Initialize the abstract base class.
            base.Initialize(name, config);

            _applicationName = GetConfigValue(config, "applicationName", System.Web.Hosting.HostingEnvironment.ApplicationVirtualPath);

            var ConnectionStringSettings = WebConfigurationManager.ConnectionStrings[config["connectionStringName"]];

            if ((ConnectionStringSettings == null) || (string.IsNullOrWhiteSpace(ConnectionStringSettings.ConnectionString.Trim())))
            {
                throw new ProviderException("Connection string cannot be blank.");
            }

            _connectionString = ConnectionStringSettings.ConnectionString;
        }


        /// <summary>
        /// Gets the configuration value.
        /// </summary>
        /// <param name="configValue">The configuration <c>NameValueCollection</c>.</param>
        /// <param name="defaultValue">The default value.</param>
        /// <returns></returns>
        private string GetConfigValue(NameValueCollection configuration, string key, string defaultValue)
        {
            if (configuration == null || String.IsNullOrEmpty(key))
            {
                return defaultValue;
            }

            return configuration[key];
        }


        #endregion

    }
}