title: add extra option to an already populated dropdownlist in mvc
body: <p>I have an html dropdownlistfor which is being populated from my database, this I was able to do successfully but the issue I am having now is including an additional option not available in the database as an option that can also be selected.it is actually a list of items but I want a give an option ALL which when selected means the user is selecting all the items displayed in the database, my major issue is how to include the ALL option. I have searched and read similar questions but they are not what am trying to achieve. thanks for your help. here is my code
  in my controller I have this:</p>
  
  <pre><code>var load = from bh in db.IV_001_ITEM
                             select bh;
                 ViewBag.selection = new SelectList(load.ToList(), "item_code", "item_name", glay.vwstring2);
  </code></pre>
  
  <p>in my view I have this:</p>
  
  <pre><code>&lt;div class="col-sm-2"&gt;
                   @Html.DropDownListFor(m =&gt; m.vwstring2, ViewBag.selection as SelectList, "Select", new { @class = "form-control", required = "required", id = "selectc" } )
          &lt;/div&gt;
  </code></pre>