ASP.NET MVC: on button click, call display multiple ActionResults in different windows

I have a form that has a drop-down list of values and a submit button.

Currently, when you click on the submit button, a stored procedure is called and then the application generates a url and then the ActionResult is a Redirect to a new window. The url is based on the currently selected value in the dropdown list.

Our client wants another button that when clicked, will basically do the same thing, but FOR ALL VALUES in the drop down list. Basically, on click, multiple windows will be opened, whose urls each based on a value in the drop down list.

I just started working with MVC and research confused me even more. I'm hoping someone can point me in the right direction. Should I handle this via some sort of loop in javascript? How? Can you give some examples, please?

ASPX Portion:

<div id="MyContainer" class="select-report">
  <%
    using (Html.BeginForm(MyManager.Query.Actions.GenerateReport(null), FormMethod.Post, new{target="_blank"}))
    {%>
      <select name="SearchText" class="my-values-select">
        <% foreach (var cc in Model.MyCentresList)
           {%>
        <option value="<%=Html.Encode(cc.Name) %>">
          <%=Html.Encode(cc.Name) %></option>
        <% }  %>
      </select>
      <input type="hidden" name="SearchType" value="MyCentre" />
      <input type="submit" value="Generate" name="EntityName" />                                          
  <% } %>      
</div>

Code-Behind:

public virtual ActionResult GenerateReport(GenerateReportOperation operation)
    {
        string entityName = operation.SearchText;
        int entityType = (int)operation.SearchType;

        string requestID1 = <code here that calls a stored procedure, a value is returned>;
        string requestID2 = <code here that calls a stored procedure, a value is returned>;

        string urlString = <code here that contructs the URL based on the values of entityName, entityType, requestID1, requestID2>;

        return Redirect(urlString);
    }