checkbox and datalist

Question

Good day to all.
I have datalist and checkbox in my web page.Datalist display a image from one folder,in datalist is a checkbox with the name of image.
I won't delete a image where checkbox is checked pushing a button but i can't catch it.IF you now please help my,i be gratefull.
there is the code and sorry for my english.

<asp:DataList ID="DataList1" runat="server">

                <ItemTemplate>

                    <div style="margin: 10px; float: left;">

                        <img alt="" src="../slike/<%# Eval("slika") %>" width="100" height="100" /><br />

                       <asp:CheckBox ID="CheckBox1" runat="server" Text='<%#Eval("ime") %>' /> 

        

                    </div>

                </ItemTemplate>

                <ItemStyle BackColor="#FFF7E7" ForeColor="#8C4510" />

                <SelectedItemStyle BackColor="#738A9C" Font-Bold="True" ForeColor="White" />

            </asp:DataList>

            <asp:Button ID="Button3" runat="server" Text="Button" onclick="Button3_Click" /> 

 protected void Button3_Click(object sender, EventArgs e)

    {

       

       

        foreach (DataListItem li in DataList1.Items)

        {

            

            CheckBox cb = (CheckBox)li.FindControl("CheckBox1");

            if (cb.Checked)

            {

                File.Delete(Server.MapPath("~/slike/" + cb.Text ));

            }

               

            

        } 

       

        pokazislike();

    }

thx in advance