[asp.net] Select multiple value in DropDownList using ASP.NET and C#

Select multiple value in DropDownList using ASP.NET and C#. I tried it to select single value from drop down but unable to find multiple selection.

Dropdown list wont allows multiple item select in dropdown.

If you need , you can use listbox control..

ASP.NET List Box

Take a look at the ListBox control to allow multi-select.

<asp:ListBox runat="server" ID="lblMultiSelect" SelectionMode="multiple">
            <asp:ListItem Text="opt1" Value="opt1" />
            <asp:ListItem Text="opt2" Value="opt2" />
            <asp:ListItem Text="opt3" Value="opt3" />
</asp:ListBox> 

in the code behind

foreach(ListItem listItem in lblMultiSelect.Items)
    {
       if (listItem.Selected)
       {
          var val = listItem.Value;
          var txt = listItem.Text; 
       }
    }

In that case you should use ListBox control instead of dropdown and Set the SelectionMode property to Multiple

<asp:ListBox runat="server" SelectionMode="Multiple" >
  <asp:ListItem Text="test1"></asp:ListItem>
  <asp:ListItem Text="test2"></asp:ListItem>
  <asp:ListItem Text="test3"></asp:ListItem>
</asp:ListBox>

For multiple selection dropdown list,cannot accomplish it directly using dropdown..Can be done in similar ways..

Either you have to use checkbox list or listbox (ajax inclusive)

http://www.codeproject.com/Articles/55184/MultiSelect-Dropdown-in-ASP-NET

http://social.msdn.microsoft.com/Forums/vstudio/en-US/54374df7-5a54-42bc-83b8-ad5994cb634d/multi-select-dropdownlist

http://www.dotnetfunda.com/articles/article1591-multiselect-dropdownlist-in-aspnet-using-csharp-40-.aspx