Why can't get the correct dropdownlist value in asp.net

Question

I have the following codes in asp.net:

<asp:dropdownlist id="ddlApp" runat="server" /> <asp:button id="btnSmt" runat="server" Text="Submit" /> 

and the code behind:

  private void btnSmt_Click(object sender, System.EventArgs e) { lbl.Text = ddlApp.SelectedItem.Value; } 

The logic is very simple. Get the selected value of the dropdown list and pass it to lbl.text.

But the problem no matter how I try, the text shows the first value of the list in the drop-down list, not the selected value.

And I notice that every time I click the page refresh button.

Please, help.

By the way, I have the following event binding:

 private void InitializeComponent() { this.btnSmt.Click += new System.EventHandler(this.btnSmt_Click); this.Load += new System.EventHandler(this.Page_Load); this.ddlApp.SelectedIndexChanged +=new System.EventHandler(this.ddlApp_Change); } 

Answer 1

You must bind to the dropdown in

 if (!Page.IsPostBack) 

Otherwise, it will rebuild the items for the drop-down list at each postback and therefore only return the selected item in the new collection - this is the first.

It also looks like you are missing btnSmt_Click on a button, but you probably installed it somewhere else ...

Answer 2

At first you debugged this ??? The reason is that C # code seems to be root.

Try changing this:

 <asp:button id="btnSmt" runat="server" Text="Submit" /> 

For

 <asp:button id="btnSmt" runat="server" Text="Submit" OnClick="btnSmt_Click" /> 

If this is really your code, your click event would never be caught, so if you put a breakpoint in your C # code, you would see that the action does not fire.

Anyway, hope this helps