In this blog we will know how to Compare Two columns values
in database and show the output in a Gridview.
Table creation
Create two tables named as t1 and t2 having id column each
on both the tables.
Table t1 Table t2
id id
1 3
2
4
3
5
4
6
Default.aspx code
<%@ Page Language="C#" AutoEventWireup="true"
CodeFile="Default.aspx.cs"
Inherits="_Default"
%>
<!DOCTYPE html
PUBLIC "-//W3C//DTD
XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form
id="form1"
runat="server">
<div>
<asp:GridView ID="GridView1"
runat="server"
ForeColor="#FF3300">
</asp:GridView>
<asp:Button ID="btnc_1to2"
runat="server"
Text="compare
column1's values with column2" onclick="btnc_1to2_Click"
Width="250px" /><br />
<asp:GridView ID="GridView2"
runat="server"
ForeColor="#663300">
</asp:GridView>
<asp:Button ID="btnc_2to1"
runat="server"
Text="compare
column2's values with column1" onclick="btnc_2to1_Click"
Width="250px" />
</div>
</form>
</body>
</html>
Default.aspx.cs code
using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using
System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
public partial
class _Default
: System.Web.UI.Page
{
string strConnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
string str;
SqlCommand com;
protected void btnc_1to2_Click(object
sender, EventArgs e)
{
SqlConnection con = new SqlConnection(strConnString);
con.Open();
str = "select * from t1
except select * from t2";
com = new SqlCommand(str, con);
SqlDataReader reader =
com.ExecuteReader();
GridView1.DataSource = reader;
GridView1.DataBind();
con.Close();
}
protected void btnc_2to1_Click(object
sender, EventArgs e)
{
SqlConnection con = new SqlConnection(strConnString);
con.Open();
str = "select * from t2
except select * from t1";
com = new SqlCommand(str, con);
SqlDataReader reader =
com.ExecuteReader();
GridView2.DataSource = reader;
GridView2.DataBind();
con.Close();
}
}
Output
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Thanks for reading