Show data in sqlserver using web.config file with the disconnected mode architecture in ASP.Net with C#

*These namespaces are must be required for SqlServer Connectivity in your web form:-

using System.Data;

using System.Data.SqlClient;

using System.Configuration;

Default3.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default3.aspx.cs" Inherits="ShowDataOnePage2010.Default3" MasterPageFile="~/Site.Master" %>

<asp:Content ID="Content1" runat="server" contentplaceholderid="MainContent">

    <table class="style1">

            <tr>

                <td align="center" colspan="4"

                   

                    style="font-family: Georgia; font-size: small; font-weight: bold; color: #800000;">

                    Registration Form</td>

            </tr>

            <tr>

                <td>

                    RegistrationID :</td>

                <td>

                    <asp:TextBox ID="txtRegistrationId" runat="server"></asp:TextBox>

                </td>

                <td>

                    <asp:Button ID="btnSubmit" runat="server" BackColor="#CCCCCC" Font-Bold="True"

                        onclick="btnSubmit_Click" Text="User_ID" />

                </td>

                <td>

                    &nbsp;</td>

            </tr>

            <tr>

                <td>

                    Name :</td>

                <td class="style2">

                    <asp:TextBox ID="txtName" runat="server"></asp:TextBox>

                </td>

                <td>

                    &nbsp;</td>

                <td>

                    &nbsp;</td>

            </tr>

            <tr>

                <td>

                    Address :</td>

                <td class="style2">

                    <asp:TextBox ID="txtAddress" runat="server"></asp:TextBox>

                </td>

                <td>

                    &nbsp;</td>

                <td>

                    &nbsp;</td>

            </tr>

            <tr>

                <td>

                    Mobile No :</td>

                <td class="style2">

                    <asp:TextBox ID="txtMobileNo" runat="server"></asp:TextBox>

                </td>

                <td>

                    &nbsp;</td>

                <td>

                    &nbsp;</td>

            </tr>

            <tr>

                <td>

                    Course :</td>

                <td class="style2">

                    <asp:CheckBoxList ID="CheckBoxList1" runat="server" Font-Bold="True">

                        <asp:ListItem>MCA</asp:ListItem>

                        <asp:ListItem>MBA</asp:ListItem>

                        <asp:ListItem>B.Tech</asp:ListItem>

                        <asp:ListItem>CA</asp:ListItem>

                    </asp:CheckBoxList>

                    <b>Course :</b>&nbsp;

                    <asp:Label ID="lblMsg2" runat="server" Font-Bold="True"></asp:Label>

                </td>

                <td>

                    &nbsp;</td>

                <td>

                    &nbsp;</td>

            </tr>

            <tr>

                <td>

                    Sex :</td>

                <td class="style2">

                    <asp:RadioButton ID="radioMale" runat="server" Font-Bold="True" GroupName="sex"

                        Text="Male" />

                </td>

                <td>

                    <asp:RadioButton ID="radioFemale" runat="server" Font-Bold="True"

                        GroupName="sex" Text="Female" />

                </td>

                <td>

                    <b>Gender :</b><asp:Label ID="lblSex" runat="server" Font-Bold="True"></asp:Label>

                </td>

            </tr>

            <tr>

                <td>

                    Email ID</td>

                <td class="style2">

                    <asp:TextBox ID="txtEmailId" runat="server"></asp:TextBox>

                </td>

                <td>

                    &nbsp;</td>

                <td>

                    &nbsp;</td>

            </tr>

            <tr>

                <td colspan="4">

                    <asp:Label ID="lblMsg" runat="server"></asp:Label>

                </td>

            </tr>

            <tr>

                <td colspan="4">

                    <asp:GridView ID="GridView1" runat="server" PageSize="3" CellPadding="4"

                        ForeColor="#333333" GridLines="None">

                        <AlternatingRowStyle BackColor="White" />

                        <FooterStyle BackColor="#990000" Font-Bold="True" ForeColor="White" />

                        <HeaderStyle BackColor="#990000" Font-Bold="True" ForeColor="White" />

                        <PagerStyle BackColor="#FFCC66" ForeColor="#333333" HorizontalAlign="Center" />

                        <RowStyle BackColor="#FFFBD6" ForeColor="#333333" />

                        <SelectedRowStyle BackColor="#FFCC66" Font-Bold="True" ForeColor="Navy" />

                        <SortedAscendingCellStyle BackColor="#FDF5AC" />

                        <SortedAscendingHeaderStyle BackColor="#4D0000" />

                        <SortedDescendingCellStyle BackColor="#FCF6C0" />

                        <SortedDescendingHeaderStyle BackColor="#820000" />

                    </asp:GridView>

                </td>

            </tr>

            <tr>

                <td align="center">

                    <asp:Button ID="btnSave" runat="server" BackColor="#CCCCCC" Font-Bold="True"

                        Text="Save" onclick="btnSave_Click" />

                </td>

                <td align="center" class="style2">

                    <asp:Button ID="btnUpdate" runat="server" BackColor="#CCCCCC" Font-Bold="True"

                        Text="Update" onclick="btnUpdate_Click" />

                </td>

                <td align="center">

                    <asp:Button ID="btnDelete" runat="server" BackColor="#CCCCCC" Font-Bold="True"

                        Text="Delete" onclick="btnDelete_Click" />

                </td>

                <td align="center">

                    <asp:Button ID="btnShow" runat="server" BackColor="#CCCCCC" Font-Bold="True"

                        Text="Show" onclick="btnShow_Click" />

                </td>

            </tr>

        </table>

</asp:Content>

<asp:Content ID="Content2" runat="server" contentplaceholderid="HeadContent">

    <style type="text/css">

        .style1

        {

            width: 522px;

            margin-left: 243px;

        }

    </style>

</asp:Content>

Web.Config File

<?xml version="1.0"?>

<configuration>

  <appSettings>

    <add key="ConnectionString" value="Server=PRADEEP-HP;Database=Decofloore2;User Id=User_006;password=user006"/>

   </appSettings>

</configuration>

Default3.aspx.cs Page

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Data;

using System.Data.SqlClient;

using System.Configuration;

namespace ShowDataOnePage2010

{

    public partial class _Default : System.Web.UI.Page

    {

       

        string Course;

        protected void Page_Load(object sender, EventArgs e)

        {

            if (!Page.IsPostBack)

            {

                lblMsg.Text = "";

            }

        }

protected void btnShow_Click(object sender, EventArgs e)

        {

            string StrCon = ConfigurationManager.AppSettings["ConnectionString"];

            SqlConnection SqlConn = new SqlConnection(StrCon);

            string SqlQuery = "Select * from ShowOnePage";

            SqlDataAdapter da = new SqlDataAdapter(SqlQuery, SqlConn);

            DataTable dt = new DataTable("ShowOnePage");

            da.Fill(dt);

            SqlConn.Open();

            if (dt.Rows.Count > 0)

            {

                GridView1.DataSource = dt;

                GridView1.DataBind();

            }

        }

  }

}

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