if user insert data and click on "SUBMIT Button" then popup msg come with "YES" or "NO" msg
<%@ Page Language="C#" AutoEventWireup="true" Codefile="It_Comp.aspx.cs" Inherits="OCMS.It_Comp" %>
    <script type="text/javascript">
        function Confirm() {
            var confirm_value = document.createElement("INPUT");
            confirm_value.type = "hidden";
            confirm_value.name = "confirm_value";
            if (confirm("Do you want to save data?")) {
                confirm_value.value = "Yes";
            } else {
                confirm_value.value = "No";
            }
            document.forms[0].appendChild(confirm_value);
        }
    </script>
<body class="auto-style21">
<form id="form1" runat="server">    
    <table width="100%" height="30" border="1" cellpadding="1" cellspacing="1" align="center"  bgcolor="#99CCCC" bordercolor="#000000">
        <tr bgcolor="#3090C7">
            <td class="auto-style4"><img src="img/m1.png" class="auto-style1" />
            </td>
            <th colspan="5" class="auto-style3">
                <u><span class="auto-style8">
                    <font color="white" class="auto-style9"><strong class="auto-style12">COMPLAINT MANAGEMENT SYSTEM</strong></font></span></u>
                <marquee attribute_name="attribute_value" class="auto-style24" >For any assistance please contact 3126 or mail to munplit@ntpc.co.in</marquee>
             </th>
                 <th class="auto-style3">
                                    
                Date:<br /> <asp:Label ID="LabelD" runat="server" Text="" CssClass="auto-style24"></asp:Label><br />
                   <asp:Label ID="lblIP" runat="server" Font-Bold="true" Font-Size="Large" ForeColor="#FFFF12" CssClass="auto-style18"/><br />
                      <br />
  <asp:LinkButton ID="LinkButton1" runat="server" OnClick="LinkButton1_Click" CssClass="auto-style7" CausesValidation="false">BACK</asp:LinkButton>
               
                 <br />                
            </th>
        </tr> 
    </table>
    <table width="100%" height="30" border="1" cellpadding="1" cellspacing="1" align="center"  bgcolor="#99CCCC" bordercolor="#000000">
        <tr>
            <td><h4 class="auto-style17">COMPLAINT TYPE</h4>
               <asp:TextBox ID="ReadOnlyTextBox" runat="server" 
     ReadOnly="True">IT COMPLAINT</asp:TextBox>
               </td>
            <td>
                <h4>COMPLAINT CATEGORY</h4>
                <select name="cat" size="1" onchange="redirect(this.options.selectedIndex);SetMessage();">
                    <option value="0" selected="selected">Select a category</option>
                    <option value=""></option>
                    <option value="--">-----------------------------------------</option>
                    <option value="PC -">PC</option>
                    <option value="Printer -">Printer</option>
                </select>
            </td>
            <td>
                <div name="dvPrinter" style="display: none;">
                    <h4>PRINTER TYPE:</h4>
                    <select name="printer" size="1" onchange="SetMessage()">
                        <option value="0" selected="selected">Select a category</option>
                        <option value=""></option>
                        <option value="--">-----------------------------------------</option>
                        <option value="Personal -">Personal</option>
                        <option value="Common -">Common</option>
                    </select>
                </div>
            </td>
            <td class="auto-style26">
                <h4>TYPE</h4>
                <select name="type" size="1" onchange="SetMessage()"></select>
            </td>
            <td>
                <div name="Location">
                    <h4>LOCATION:</h4>
                    <select name="Location" size="1" onchange="SetMessage()" class="auto-style20">
                        <option value="0" selected="selected">Select a Location</option>
                        <option value=""></option>
                        <option value="--">-----------------------------------------</option>
                        <option value="H-type">H-type</option>
                        </select>
                </div>
 <td>
    <div name="room">
          <h4>Building/Room/Hall:</h4>
        
      <asp:TextBox ID="room" runat="server" onchange="SetMessage()" placeholder="room/hall"></asp:TextBox>
        </div>
        </td>
 
            <td>
                <h4>Image File:(Only image File (jpg,png))</h4>
                <asp:FileUpload ID="FileUpload1" runat="server" />
            </td>
        </tr>
 <tr bgcolor="#3090C7">
        <u>
            <font color="#FFFF12" >
            <h3 align="left"  >IT Complaint box:    
                </font>
                <strong>
                    <font color="white" >
                    Emp. Id:
                    <asp:Label ID="lblName" runat="server" Text="Label"></asp:Label>   
                     Mob.No:
                    <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>  
                        
                    <asp:Label ID="txtrowid" runat="server" Text=""></asp:Label>
                  </font>
                </strong>
            </h3>
        </u></tr>
     
        <table width="100%" height="30" border="1" cellpadding="1" cellspacing="1" align="center"  bgcolor="#99CCCC" bordercolor="#000000">
            <br />
            <tr>
                <td width="120" scope="col">
                    <center><b>COMPLAINT MESSAGE </b></center>
                </td>
                <td>
                    <asp:TextBox runat="server" ID="str" TextMode="Multiline" Columns="20" Name="S1" Rows="2" CssClass="auto-style10" Height="140px" Width="1154px"></asp:TextBox><br />
                     <asp:RequiredFieldValidator ID="RequiredFieldValidator" runat="server" ErrorMessage="**Complaint message Can't be blank**" ControlToValidate="str" ForeColor="Red"></asp:RequiredFieldValidator>  
                    <center><asp:Button ID="Button1" runat="server" Text="Submit" OnClick="Button1_Click" CssClass="auto-style15" Height="26px" Width="83px" OnClientClick="Confirm()" ></asp:Button></center>
                </td>
            </tr>
        </table>
        <div id="dialog" style="display: none"></div>
        </div>
    </table>
</form>
 
protected void Button1_Click(object sender, EventArgs e)
{
    string employeeId = lblName.Text.Trim();
    string message = str.Text.Trim();
    string ReadOnly = ReadOnlyTextBox.Text.Trim();
    string COMP_LODGE_DATE = DateTime.Now.ToString("yyy/dd/mm");
    string image = "";
    if (FileUpload1.HasFile)
    {
        string fileName = Path.GetFileName(FileUpload1.PostedFile.FileName);
        if (!Directory.Exists(Server.MapPath("~/Images")))
        {
            Directory.CreateDirectory(Server.MapPath("~/Images"));
        }
        FileUpload1.PostedFile.SaveAs(Server.MapPath("~/Images/") + fileName);
        image = "~/Images/" + fileName;
    }
    string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    string query = "insert_ittest1";
    using (SqlConnection con = new SqlConnection(conString))
    {
        SqlCommand cmd = new SqlCommand(query);
        cmd.Parameters.AddWithValue("@EMP_ID", employeeId);
        cmd.Parameters.AddWithValue("@COMP_MESSAGE", message);
        cmd.Parameters.AddWithValue("@Comp_type", ReadOnly);
        cmd.Parameters.AddWithValue("@COMP_LODGE_DATE", COMP_LODGE_DATE);
        cmd.Parameters.AddWithValue("@image", image);
        cmd.Parameters.Add("@COMP_ID", SqlDbType.Int).Direction = ParameterDirection.Output;
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Connection = con;
        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
        con.Dispose();
    }
}