Can't add items from listbox to list - asp.net

Question

I am trying to add all items from a listbox to list(.cs page).I added items to listbox using javascript.Now LstScan.Items.Count return zero always.I can't add items to listbox.Listbox shows values.but problem happens in my .cs file.
here is my code;
Html and javascript Code is:
<script type="text/javascript">
function displayKeyCode_demo(e) {
var code;
if (!e) var e = window.event;
if (e.keyCode) code = e.keyCode;
else if (e.which) code = e.which;
if (code == 13) {
var textbox = document.getElementById("<%=TextBox1.ClientID%>")
var listbox = document.getElementById("<%=LstScan.ClientID%>")
var newOption = document.createElement("Option");
newOption.value = textbox.value;
newOption.innerHTML = textbox.value;
listbox.add(newOption);
}
}
</script>
<div>
<table cellspacing="3px" style="margin: 10px auto 3px 85px;">
<tr>
<td width="150px">
<asp:TextBox ID="TextBox1" runat="server" onkeypress="displayKeyCode_demo(event)"></asp:TextBox>
</td>
<td width="200px">
<asp:ListBox ID="LstScan" runat="server" Height="200px" Width="150px" AppendDataBoundItems="True" AutoPostBack="True" >
</asp:ListBox>
</td>
</tr>
</table>
</div>
here is my code behind code:
List<int> LstSOnum = new List<int>();
foreach (ListItem item in LstScan.Items) {
LstSOnum.Add(int.Parse(item.Value));
}

Answer 1

You can try with Text
LstSOnum.Add(int.Parse(item.Text));