Passing multiple parameters from url to html.actionlink

Question

I'm fairly new to MVC and am struggling with routing when I try to pass multiple parameters via the URL.

From a page with the URL: /PersonCAFDetail/Index/3?memberid=4

...I'm trying to get an Html.ActionLink set to point to the Create action such that the id=3 and the memberid=4.

Having read a number of similar posts it seems that the following should work:

@Html.ActionLink("Create New", "Create", null, new { memberid = "memberid" })

However, this results in a URL being created as follows:

<a href="/PersonCAFDetail/Create/3" memberid="memberid">Create New</a>

I have a route set up as:

    routes.MapRoute(
        name: "PersonCAFDetail",
        url: "PersonCAFDetail/Create/{id}/{memberid}",
        defaults: new { controller = "PersonCAFDetail", action = "Create", id = "@\d+", memberid = @"\d+" }                        
        );

The controller accepts two parameters as follows:

 public ActionResult Create(int id, int memberid)
        {
            int cafID = id;
            int personID = memberid;
            ViewBag.detailTypeID = new SelectList(db.tCAFDetailTypes, "detailTypeID", "detailType");
            ViewBag.cafID = new SelectList(db.tFamilyCAFs, "cafID", "issues");
            ViewBag.personID = new SelectList(db.tPersons, "personID", "forename");
            return View();
        }

Any help appreciated.

-------edit for model----------

namespace WhatWorks.Models
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    using System.ComponentModel.DataAnnotations;

    public partial class tPersonCAFDetail
    {
        [Key, HiddenInput(DisplayValue=false)]
        public int cafID { get; set; }

        [Key, HiddenInput(DisplayValue = false)]
        public int personID { get; set; }

        [Key, HiddenInput(DisplayValue = false)]
        public int detailTypeID { get; set; }

        [Required, DataType(DataType.MultilineText)]
        public string notes { get; set; }


        public string FullName
        {
            get
            {
                return tPerson.forename + " " + tPerson.surname;
            }
        }

        public virtual tCAFDetailType tCAFDetailType { get; set; }
        public virtual tFamilyCAF tFamilyCAF { get; set; }
        public virtual tPerson tPerson { get; set; }
    }
}

Solution

Finally, you need pass two parameters to the view:

Index action:

public ActionResult Index(int id, int memberid)
{
    ...
    ViewBag.cafID = id;
    ViewBag.personID = memberid;
    return View();
}

Index.cshtml

@Html.ActionLink("Create New", "Create", "PersonCAFDetail", new { id=ViewBag.cafID , memberid =ViewBag.personID}, null)

And Check your route syntax... id = @"\d+"

 routes.MapRoute(
    name: "PersonCAFDetail",
    url: "PersonCAFDetail/Create/{id}/{memberid}",
    defaults: new { controller = "PersonCAFDetail", action = "Create", id = @"\d+", memberid = @"\d+" }                        
    );