R – MVC2 ViewData Problems

asp.net-mvc-2model-view-controller

I'm trying to pass a list of a few items to a view via the ViewData to create a drop down list. This shouldn't be too difficult, but I'm new to MVC, so I'm probably missing something obvious.

The controller assigns the list to the ViewData:

ViewData["ImageLocatons"] = new SelectList(gvr.ImageLocations);

and the view tries to render it into a drop down list:

<%= Html.DropDownList("Location", ViewData["ImageLocations"] as SelectList) %>

However, when I run it, I get this error:
There is no ViewData item of type 'IEnumerable' that has the key 'Location'.

Any ideas why this isn't working? Also, shouldn't it be looking for the key "ImageLocations" rather than location?

Best Answer

If you use:

ViewData["Location"] = new SelectList(gvr.ImageLocations);

and

<%= Html.DropDownList("Location") %>

Your life will be a lot easier.

Also check out the typo (missing i) when setting the ViewData in your example (ImageLocatons => ImageLocations). This causes the second parameter you pass to DropDownList to be null. This will cause the MVC engine to search for Location.

Related Solutions

Javascript – Populating dropdownlist with selectlist in ViewData

Locations is a select and doesn't have a value property. To get the value of the selected option you need to use the selected index, find the correct option, and reference the value of the option. If you use jQuery you can, however, it will get the value of a select using the val() method of the jQuery object. I suggest jQuery since it will make the code simpler and MS will be supporting it with Visual Studio.

Example using jQuery:

<script type='text/javascript'>
    $(document).ready( function() {
       $('form').submit( function() {
          var fromAddress = $(this).find('#from').val();
          var toAddress = $(this).find('#locations').val();
          var locale = 'en-US';

          ....
          return false;
       });
    });
</script>

  <form action="#">

    <table>
    <tr><th align="left">From: </th>

    <td align="left" ><input type="text" id="fromAddress" name="from" size="35px"
    value="King of Prussia, PA"/></td>
    <th align="left">  To: </th>
    <td align="left"> <%= Html.DropDownList("locations",(SelectList)ViewData["OfficeLocations"])%></td>

    ...

R – Dropdownlist value not getting set from SelectList passed to view in ViewData

I had to upgrade to MVC RC2 from preview 4. It addressed drodownlist issues and fixed my problem.

Best Answer

Related Solutions

Javascript – Populating dropdownlist with selectlist in ViewData

R – Dropdownlist value not getting set from SelectList passed to view in ViewData

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