.NET Full Framework BasicAuthentication

    public class BasicAuthenticationAttribute : AuthorizationFilterAttribute

    {

        public override void OnAuthorization(System.Web.Http.Controllers.HttpActionContext actionContext)

        {

            if (actionContext.Request.Headers.Authorization == null)

            {

                actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized);

            }

            else

            {

                // Gets header parameters 

                string authenticationString = actionContext.Request.Headers.Authorization.Parameter;

                string originalString = Encoding.UTF8.GetString(Convert.FromBase64String(authenticationString));

                // Gets username and password 

                string useranme = originalString.Split(':')[0];

                string password = originalString.Split(':')[1];

                // Validate username and password 

                if (!(useranme.Equals(System.Configuration.ConfigurationManager.AppSettings["Authorization_username"].Trim()) &&

                    password.Equals(System.Configuration.ConfigurationManager.AppSettings["Authorization_password"].Trim())))

                {

                    // returns unauthorized error 

                    actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.Unauthorized);

                }

            }

            base.OnAuthorization(actionContext);

        }

    }


[BasicAuthentication]
    public class ValuesController : ApiController
    {
        // GET api/values
        public IEnumerable<string> Get()
        {
            return new string[] { "value1", "value2" };
        }