Search an ASP.NET DropDownList

A user mailed me recently asking me the simplest way to search an ASP.NET DropDownList. I think the simplest way is using the foreach loop as shown below (although it may be slow when the items are huge):

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:DropDownList ID="DropDownList1" runat="server">
            <asp:ListItem Text="Item1"></asp:ListItem>
            <asp:ListItem Text="Item2"></asp:ListItem>
            <asp:ListItem Text="Item3"></asp:ListItem>
        </asp:DropDownList>
        <br />
        <asp:Button ID="btnSearch" runat="server" Text="Search"
            onclick="btnSearch_Click"/>
    </div>
    </form>
</body>
</html>

C#

protected void btnSearch_Click(object sender, EventArgs e)
{
    string str = "Item2";
    // Using For Each
    foreach (ListItem li in DropDownList1.Items)
    {
        if (li.Value == str)
        {
            this.DropDownList1.SelectedValue = li.Value.ToLower();
               
        }
    }       
}

VB.NET

Protected Sub btnSearch_Click(ByVal sender As Object, ByVal e As EventArgs)
    Dim str As String = "Item2"
    ' Using For Each
    For Each li As ListItem In DropDownList1.Items
        If li.Value = str Then
            Me.DropDownList1.SelectedValue = li.Value.ToLower()

        End If
    Next li
End Sub
The code shown above loops through all the items of a DropDownList and selects the item if the string is found. To make the code case insensitive, use ToLower()/ToUpper() and compare the values.

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