在ASP.NET MVC5中编辑连接表时完成下拉列表

Question

        if (q != null)
        {
            return View(q);
        }
        else
        {
            return RedirectToAction("ShowPerson", "Home");
        }
    }


    [HttpPost]
    public ActionResult EditPerson(Person per)
    {
        var q = (from a in db.Person
                 where a.ID.Equals(per.ID)
                 select a).SingleOrDefault();

        q.FirstName = per.FirstName;
        q.LastName = per.LastName;
        q.UserName = per.UserName;
        q.EvidenceID = per.EvidenceID;
        q.Mobile = per.Mobile;
        q.Stutus = false;
        q.CodeMelli = per.CodeMelli;
        q.CityID = per.CityID;
        q.Address = per.Address;
        q.Access = per.Access;
        q.Email = per.Email;
        q.Image = per.Image;

        db.Person.Attach(q);
        db.Entry(q).State = System.Data.Entity.EntityState.Modified;
        db.SaveChanges();

        return RedirectToAction("ShowPerson", "Home");
    }


    [HttpGet]
    public ActionResult CreatePerson()
    {

        return View();
    }


    [HttpPost]
    public ActionResult CreatePerson(Person per)
    {
        Person p = new Person();

        p.FirstName = per.FirstName;
        p.LastName = per.LastName;
        p.UserName = per.UserName;
        p.EvidenceID = per.EvidenceID;
        p.Mobile = per.Mobile;
        p.Stutus = false;
        p.CodeMelli = per.CodeMelli;
        p.CityID = per.CityID;

        p.Address = per.Address;
        p.Access = per.Access;
        p.Email = per.Email;
        p.Image = per.Image;

        db.Person.Add(p);
        db.SaveChanges();

        return RedirectToAction("ShowPerson", "Home");
    }

        <div class="form-group">

@html.labelfor（模型=>model.cityid,htmlAttributes:new{@class=“control-label col-MD-2”}）@html.editorfor（模型=>model.cityid,new{htmlAttributes=new{@class=“form-control”}}）@html.validationmessagefor（模型=>model.cityid,“”,new{@class=“text-danger”}）

        <div class="form-group">

@html.labelfor（模型=>model.evidenceid,htmlAttributes:new{@class=“control-label col-MD-2”}）@html.editorfor（模型=>model.evidenceid,new{htmlAttributes=new{@class=“form-control”}}）@html.validationmessagefor（模型=>model.evidenceid,“”,new{@class=“text-danger”}）

Answer 1

你的问题没有被理解，但你需要的是一个从三个不同的模型下拉列表，因为我猜...

在您自己的域中尝试此操作：

var dataForDL = _db.ModelName.Select(a => new
                {
                   Text = a.PersonName +" "+ a.Evidence.Name +" "+ a.City.CityName,
                   Value = a.Id
                }).ToList();
ViewBag.DropdownListForModel = new SelectList(dataForDL, "Value", "Text");

在view.cshtml中

@Html.DropDownList("DropdownListForModel", null, "-- Please Select Something --", htmlAttributes: new { @class = "form-control" })