DropDownList Selected Index change

Question

I am using DropDownList inside Updatepanel with its autopost back property set to true, its working fine except when it has SelectedValue=0(ie SelectedIndex=0)

here's my drop down list

<asp:UpdatePanel ID="panel" runat="server">
    <ContentTemplate>
        <asp:DropDownList ID="ddFilter" EnableViewState="false" runat="server" Style="width: 168px;
            border: none;" OnSelectedIndexChanged="ddComapanyFilter_SelectedIndexChanged"
            AutoPostBack="true">
            <asp:ListItem Text="All" Value="0"></asp:ListItem>
            <asp:ListItem Text="Flagged" Value="1"></asp:ListItem>
            <asp:ListItem Text="New" Value="2"></asp:ListItem>
        </asp:DropDownList>
    </ContentTemplate>
</asp:UpdatePanel>

and this is my SelectedIndexChangedEvent

protected void ddComapanyFilter_SelectedIndexChanged(object sender, EventArgs e)
{
    if (ddComapanyFilter.SelectedValue == "0")//All
    {
       //code
    }
    else if (ddComapanyFilter.SelectedValue == "1")//Flagged
    {
       //code
    }
    else if (ddComapanyFilter.SelectedValue == "2")//New
    {
       //code
    }          
}

When I select New or Flagged it works fine, but when I again select All,it don't do any thing,I have tried debugging it,in case of All its not hitting the code.

I tried by replacing my drop down code with this

<asp:DropDownList ID="ddFilter" EnableViewState="false" runat="server" Style="width: 168px;
                                border: none;" OnSelectedIndexChanged="ddComapanyFilter_SelectedIndexChanged"
                                AutoPostBack="true">
                                <asp:ListItem Text="All" Value="1"></asp:ListItem>
                                <asp:ListItem Text="Flagged" Value="2" Selected="True"></asp:ListItem>
                                <asp:ListItem Text="New" Value="3"></asp:ListItem>
                            </asp:DropDownList>

Now When I am selecting Flagged,after selecting New or All, its not hitting

Answer 1

This is a known issue in dropdownlist, always first list item doesn't fire that's why you can add a dummy listitem at the beginning like "Select.." or what ever you want to make it work

<asp:UpdatePanel ID="panel" runat="server">
    <ContentTemplate>
        <asp:DropDownList ID="ddFilter" EnableViewState="false" runat="server" Style="width: 168px;
            border: none;" OnSelectedIndexChanged="ddComapanyFilter_SelectedIndexChanged"
            AutoPostBack="true">
            <asp:ListItem Text="whatever" value=""></asp:ListItem>
            <asp:ListItem Text="All" Value="0"></asp:ListItem>
            <asp:ListItem Text="Flagged" Value="1"></asp:ListItem>
            <asp:ListItem Text="New" Value="2"></asp:ListItem>
        </asp:DropDownList>
    </ContentTemplate>
</asp:UpdatePanel>