How can I remove the double quotes after sending data to view with ViewBag?

Question

I have many to many relationship in edit page how can i show selected items selected in a Dropdown multi select

here is my code:

        // GET: Project/Edit/5
    public ActionResult Edit(int? id)
    {
        if (id == null)
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
        var edata = db.Projects.Find(id);
        //check if data
        if (edata == null)
            return HttpNotFound();

        //IEnumerable<SelectListItem> items = db.Provinces.Select(c => new SelectListItem { Value = c.ID.ToString(), Text = c.Name });
        //ViewBag.ProvinceId = items;

        //---Get all provice-----
        var Prov = from c in db.Provinces select c;
        //------get province ids---------------
        var prov_id = from o in db.ProRel where o.ProjectId == id select o.ProvinceIds;
        List<int> mid_list = new List<int>();
        foreach (var p_ids in prov_id)
        {
            mid_list.Add(p_ids);
        }
        var option_vals = "";
        var selected = string.Empty;
        foreach (var p_itmes in Prov)
        {
            if (mid_list.Contains(p_itmes.ID))
            {
                selected = "selected='selected'";
            }
            else
            {
                selected = "";
            }
            option_vals += "<option "+selected+" value="+p_itmes.ID+">"+p_itmes.Name+"</option>";
        }
        string test = option_vals.ToString();
        string test2 = test.Replace("\"", "");
        ViewBag.options = test2;
        return View(edata);
    }

in my edit view my code:

      <div class="form-group">
        <label class="control-label col-md-2">Provinces</label>
        <div class="col-md-10">
            <select name="prov" id="prov">
                @ViewBag.options
            </select>
        </div>
    </div>

it displays the option values with double quotes at the end and it does not render like Html select options how can I remove the quotes that my options should be shown in its normal mode.

when I inspect element in browser the options are shown like this:

"<option  value=1>Kabul</option><option selected='selected' value=2>Mazar</option><option selected='selected' value=3>Parwan</option><option  value=4>Herat</option><option  value=5>Badakhshan</option><option  value=6>Takhar</option><option  value=7>Smanagan</option><option selected='selected' value=8>Zabul</option>"

or you suggest me another way for this I am new to ASP.Net

You missed the quotes in the value attribute `option_vals += "";` — Marcos González, Nov 27 '14 at 14:21
This can all be done in 2 or 3 lines of code by using a view model and the model binding features of MVC — , Nov 27 '14 at 21:43

Christoph Fink · Answer 1 · 2014-11-27T16:40:35.153

2

Short answer was already given by Marcos via his comment, but in general thats not how you create a select tag within MVC 5:

Controller:

public ActionResult Edit(int? id)
{
    // other code
    var options = new List<SelectListItem>();
    foreach (var p_itmes in Prov)
    {
        var item = new SelectListItem();
        if (mid_list.Contains(p_itmes.ID))
            item.Selected = true;
        item.Value = p_itmes.ID.ToString();
        item.Text = p_itmes.Name;
        options.Add(item);
    }
    ViewBag.options = options;
    return View(edata);
}

View:

<div class="form-group">
    <label class="control-label col-md-2">Provinces</label>
    <div class="col-md-10">
        @Html.DropDownList("prov", (List<SelectListItem>)ViewBag.options,
                           htmlAttributes: new { multiple = "multiple" })
    </div>
</div>

edited Nov 27 '14 at 16:40

answered Nov 27 '14 at 14:29

Christoph Fink

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My ASP.Net says: doesn't have a does not contain a definition for 'DropDownFor' and no extension method 'DropDownFor – Benafsh Yalda Nov 27 '14 at 14:36
@BenafshYalda: My mistake (wrote that "out of my head") - see my update or http://msdn.microsoft.com/en-us/library/dd492738(v=vs.118).aspx – Christoph Fink Nov 27 '14 at 14:41
has no applicable method named 'DropDownList' but appears to have an extension method by that name. Extension methods cannot be dynamically dispatched. Consider casting the dynamic arguments or calling the extension method without the extension method syntax – Benafsh Yalda Nov 27 '14 at 15:34
My Dropdown is multi select dropdown I want that selected Items showed be shown selected – Benafsh Yalda Nov 27 '14 at 16:18
@BenafshYalda: Then you need to add the `multiple` attribute as suggested by Mehdi... – Christoph Fink Nov 27 '14 at 16:41
Thanks for your support – Benafsh Yalda Nov 27 '14 at 16:53

score 2 · Accepted Answer · answered Nov 27 '14 at 16:34

I agree with @ChrFin Answer but with some more details which I hope will solve your problem

     // GET: Project/Edit/5
    public ActionResult Edit(int? id)
    {
        if (id == null)
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
        var edata = db.Projects.Find(id);
        //check if data
        if (edata == null)
            return HttpNotFound();

        //IEnumerable<SelectListItem> items = db.Provinces.Select(c => new SelectListItem { Value = c.ID.ToString(), Text = c.Name });
        //ViewBag.ProvinceId = items;

        //---Get all provice-----
        var Prov = from c in db.Provinces select c;
        //------get province ids---------------
        var prov_id = from o in db.ProRel where o.ProjectId == id select o.ProvinceIds;
        List<int> mid_list = new List<int>();
        foreach (var p_ids in prov_id)
        {
            mid_list.Add(p_ids);
        }

        var options = new List<SelectListItem>();
        foreach (var p_itmes in Prov)
        {
            var item = new SelectListItem();
            if (mid_list.Contains(p_itmes.ID))
                item.Selected = true;
            item.Value = p_itmes.ID.ToString();
            item.Text = p_itmes.Name;
            options.Add(item);
        }
        ViewBag.options = options;
        return View(edata);

    }

and inside your view add the following extra attribute:

    <div class="form-group">
        <label class="control-label col-md-2">Provinces</label>
        <div class="col-md-10">
            @Html.DropDownList("prov", (List<SelectListItem>)ViewBag.options, htmlAttributes: new { @class = "form-control", @multiple = "multiple" })
        </div>
    </div>

How can I remove the double quotes after sending data to view with ViewBag?

2 Answers2