Question

I want to create an ‘editable’ table in MVC, where each row will have its own dropdownlist to update the row value. How do I set the dropdownlist selected value on page load for rows that were already updated before.

My current Razor code is like this:

<tbody>
   @foreach (var conversion in Model.PaginatedConversions)
   {
        <tr>
             <td>@conversion.tSystem.systemName</td>
             <td>@conversion.conversionStandardValue</td>
             <td>@Html.DropDownList("ConversionStandardIdFor" + conversion.conversionID.ToString(), Model.AvailableValuesForConversion, "")</td>
             <td>@conversion.conversionDescription</td>
             <td>@conversion.conversionDateInput</td>
             <td>@conversion.ConversionDateConverted</td>
             <td>@conversion.ConversionUser</td>
        </tr>
   }

But I cannot set the selected value of each dropdown. How can I do this? Thanks for the help!

Edit1 : This code loops a model property (Model.PaginatedConversions), which is of type List<Conversion>. The Conversion class is as followed:

public class Conversion {
    int ConversionId { get;set; }
    string ConversionValue { get; set; }
    int ConversionConvertedValue { get; set; }
}

The goal of the table is to create editable rows for user to map the ConversionValue to another value that can be selected in Model.AvailableConversionValues. This converted value will be stored in ConversionConvertedValue.

The property Model.AvailableConversionValues are of type List<SelectListItem> that contains the available values user can choose from to map the ConversionValue.

Answer 1

Passing the ConversionValue as a name didn’t work. I created another method in the ViewModel, and use that instead for getting the SelectListItem, passing the selected value to be selected in the ListItem.

<td>@Html.DropDownList("ConversionFor" + conversion.conversionID.ToString(), Model.GetAvailableConversionValues(conversion.conversionStandardID))</td>

And in the ViewModel I have this method:

public List<SelectListItem> GetAvailableConversionValues(int? selectedValue)
    {
        if (selectedValue != null)
        {
            SelectListItem selectItem = AvailableValuesForConversion.Where(t => int.Parse(t.Value) == selectedValue).SingleOrDefault();

            if (selectItem != null)
            {
                selectItem.Selected = true;
            }
        }
        return AvailableValuesForConversion;
    }

Thanks for the help!