Listbox selectedindexchange event not firing ? ASP.NET C#

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C#

ASP.NET

ListBox

Hi.
I have a listbox which reterive values from database and when i select value from lisbox then i want that page redirect to other,but I'm unable to do this,I think my code is perfect but not working.Autopostback property is 'true' but it's not firing the event .

What I have tried:

Here is my aspx code :

 <asp:ListBox ID="ListBox1" runat="server" Height="202px" Width="262px" 
        style="margin-left: 247px; margin-top: 68px" 
        onselectedindexchanged="ListBox2" AutoPostBack="true" EnableViewState="True">
</asp:ListBox>

and here is my aspx.cs code

protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            getdata();
        }
    }
    public void getdata()
    {
        string user = Session["name"].ToString();

        SqlConnection cnn = new SqlConnection("Data Source=HAMEED_KHAN\\SQLEXPRESS;Initial Catalog=db_compiler;Integrated Security=True");
        SqlCommand cmd2 = new SqlCommand("SELECT User_ID from tbl_user WHERE User_Name='" + user + "'", cnn);
        cnn.Open();
        string id = cmd2.ExecuteScalar().ToString();
        int ID = Int32.Parse(id);
        SqlCommand cmd = new SqlCommand("USE db_compiler SELECT Database_Name FROM  Create_db WHERE User_ID='" + ID + "'", cnn);
        DataTable dt = new DataTable();
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        cmd.ExecuteNonQuery();
        da.Fill(dt);
        if (dt.Rows.Count > 0)
        {
            foreach (DataRow row in dt.Rows)
            {
                string value = row["Database_Name"] + "";

                ListBox1.Items.Add(value);
            }

        }
    }
    public void ListBox2(object sender, EventArgs e)
    {
        Session["value"] = ListBox1.SelectedValue;

        Response.Redirect("CreateTable.aspx");
    }
}

Values loaded from database into listbox well,but page not redirect to other.I use break point to confirm that is event firing or not,But event not firing.Thanks