Passing Values from the SelectList Items Using ViewModel

Question

I'd like to get the values of the selected items in dropdownlists. I am saving the files into the database with the following code:

public ActionResult UploadDoc(IEnumerable<HttpPostedFileBase> files)
{
    foreach (var file in files)
    {
        if (file != null && file.ContentLength > 0)
        {
            byte[] data = new byte[file.ContentLength];
            file.InputStream.Read(data, 0, file.ContentLength);

            Document doc = new Document
            {
                UploadedOn = DateTime.Now,
                MimeType = file.ContentType,
                UserName = User.Identity.Name,
                Data = data,
                FromLanguage = 1,
                ToLanguage = 2
            };

            dbContext = new MedicalDb();
            dbContext.Documents.Add(doc);
            dbContext.SaveChanges();
        }
    }
    return RedirectToAction("Index");
}  

but, I'd also like to get the selected values from the dropdownlists so that I can populate the FromLanguage and ToLanguage properties of the documents. I guess I'd need a viewmodel, but don't know how to do it. New rows for document upload are added using jQuery and names of the ddls are "ddlFromLanguage1", "ddlFromLanguage2", "ddFromLanguage3", and "ddlToLanguage1", "ddlToLanguage2", "ddlToLanguage3", etc. Thanks in advance for any help.

<form action="UploadDoc" method="post" enctype="multipart/form-data">    
<table id="tblUploadDocs">
    <tr id="row1">
        <td><input type="file" name="files" id="file1" /></td>
        <td>Bu dilden</td>
        <td>@Html.DropDownList("ddlFromLanguage1", ViewBag.Languages as SelectList)</td>
        <td>şu dile çevrilecek</td>
        <td>@Html.DropDownList("ddlToLanguage1", ViewBag.Languages as SelectList)</td>
    </tr>
</table>
<br />
<a href="javascript:addRow();" style="margin:10px 0;">Yeni dosya ekleyin</a>
<input type="submit"  />
</form>

Answer 1

I think you need to look at good example and do the same or very similar to them.

Take a look at these:

• ASP.NET MVC 3 Viewmodel Pattern
• Implementing Dropdownlist on Asp.net MVC 3 from viewModel

These should get you going.

Please let me know if you don't succeed or if what I gave you was actually helpful.

Thanks

Answer 2

The solution:

The viewmodel:

public class CustomerDocUploadViewModel
{
    public HttpPostedFileBase File { get; set; }
    public int FromLanguage { get; set; }
    public int ToLanguage { get; set; }
}

The view:

@model IList<Models.ViewModels.CustomerDocUploadViewModel>

...

<form action="UploadDoc" method="post" enctype="multipart/form-data">    
<table id="tblUploadDocs">
    <tr id="row1">
        <td><input type="file" name="[0].File" /></td>
        <td>Bu dilden</td>
        <td>@Html.DropDownList("[0].FromLanguage", ViewBag.Languages as SelectList)</td>
        <td>şu dile çevrilecek</td>
        <td>@Html.DropDownList("[0].ToLanguage", ViewBag.Languages as SelectList)</td>
    </tr>
</table>
<br />
<a id="lnkAdd" href="javascript:addRow();" style="margin:10px 0;">Yeni dosya ekleyin</a>
<input type="submit"  />
</form>

and finally the action method in the controller:

[HttpPost]
    public ActionResult UploadDoc(IList<CustomerDocUploadViewModel> docInfos)
    {
        for (int i = 0; i < docInfos.Count; i++)
        {
            if (docInfos.ElementAt(i).File != null && docInfos.ElementAt(i).File.ContentLength > 0)
            {
                byte[] data = new byte[docInfos.ElementAt(i).File.ContentLength];
                docInfos.ElementAt(i).File.InputStream.Read(data, 0, docInfos.ElementAt(i).File.ContentLength);

                // Save the file into the database
                Document doc = new Document
                {
                    UploadedOn = DateTime.Now,
                    MimeType = docInfos.ElementAt(i).File.ContentType,
                    UserName = User.Identity.Name,
                    Data = data,
                    FromLanguage = docInfos.ElementAt(i).FromLanguage,
                    ToLanguage = docInfos.ElementAt(i).ToLanguage
                };

                dbContext = new MedicalDb();
                dbContext.Documents.Add(doc);
                dbContext.SaveChanges();
            }
        }    
        return RedirectToAction("Index");
    }     

Answer 3

Any form that is posted back returns a FormCollection to the controller in addition to model related values.

For example

  //In your view
  @using (Html.BeginForm("CountrySelect", "Country", FormMethod.Post))
            {
                @Html.AntiForgeryToken()
                <select name="country" id="country-select">
                   <option value="selector">Pick a Country</option>
                   <option value="England">England</option>
                   <option value="England">England</option> 
                </select>         
            }

//In controller
//This will get you the name of the selected country from your form
[HttpPost]
Public ActionResult CountrySelect(FormCollection formData)
{
   string country = formData["country"].toString();
}