下拉列表SelectedItems回发不存在

Question

I'm not sure what to do here, I might have to use viewstates, but I need help.

I have a dropdown list, I am not databinding. I would know if I was I should do a Page.IsPostBack and not databind.

<asp:DropDownList ID="ddlWeeklyWeightIn" runat="server">
    <asp:ListItem>1</asp:ListItem>
    <asp:ListItem>2</asp:ListItem>
    <asp:ListItem>3</asp:ListItem>
    <asp:ListItem>4</asp:ListItem>
</asp:DropDownList>

Now in my code behind I have this:

 protected void Button1_Click(object sender, EventArgs e)
    {
        string wwin = "";
        wwin = ddlWeeklyWeightIn.SelectedItem.Text;
    }

On the button click is always "1", never the selected item.

Thank you

Answer 1

尝试将EnableViewState =“ True”添加到下拉控件中。

Answer 2

A post back is causing to reset your selected value. either use if(!IsPostBack) or use update panel to prevent post back.

Answer 3

This is just to make sure but could you try using:

<asp:DropDownList ID="ddlWeeklyWeightIn" runat="server">
    <asp:ListItem Text="1"></asp:ListItem>
    <asp:ListItem Text="2"></asp:ListItem>
    <asp:ListItem Text="3"></asp:ListItem>
    <asp:ListItem Text="4"></asp:ListItem>
</asp:DropDownList>

Could you check you don't just SET the selected item during page's initialization?

Answer 4

Aspx side: add autopostback=true to dropdown property and and use listitem as following: ListItem Text="4" Value="4"> etc

Code Behind: string wwin = ""; wwin = ddlWeeklyWeightIn.SelectedValue;