Sort Items in an ASP.NET DropDownList using LINQ

Have you been looking out for a way to sort the items of an ASP.NET DropDownList using LINQ? Here’s a LINQ solution:

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Sorting DropDownList Items</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:DropDownList ID="DropDownList1" runat="server">
            <asp:ListItem Text="Item3"></asp:ListItem>
            <asp:ListItem Text="Item1"></asp:ListItem>
            <asp:ListItem Text="Item4"></asp:ListItem>
            <asp:ListItem Text="Item5"></asp:ListItem>
            <asp:ListItem Text="Item2"></asp:ListItem>
        </asp:DropDownList>
        <br />
        <asp:Button ID="btnSort" runat="server" Text="Sort"
            onclick="btnSort_Click"/>
    </div>
    </form>
</body>
</html>



C#

protected void btnSort_Click(object sender, EventArgs e)
{
List<string> listItems =
   DropDownList1.Items.Cast<ListItem>().Select(item => item.Text).ToList();
listItems.Sort((a, b) => string.Compare(a, b));
DropDownList1.DataSource = listItems;
DropDownList1.DataBind();
}

VB.NET

Protected Sub btnSort_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim listItems As List(Of String) = _
    DDL.Items.Cast(Of ListItem)().Select(Function(item) item.Text).ToList()
    listItems.Sort(Function(a, b) String.Compare(a, b))
    DDL.DataSource = listItems
    DDL.DataBind()
End Sub

Before Sorting

image

After Sorting

image

4 comments:

  1. AnonymousSeptember 23, 2009 at 12:43 AM

    great stuff. Thanks for sharing.
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    ReplyDelete
  2. Raunak JhawarJanuary 5, 2010 at 5:00 AM

    Thank you very much

    ReplyDelete
  3. AnonymousDecember 23, 2012 at 6:30 AM

    This idea works except that it destroys any value items that was part of the list.

    ReplyDelete
  4. UnknownNovember 21, 2014 at 7:04 AM

    Does anyone have a solution for losing the values portion of the list items?

    ReplyDelete