Display rows data from selected DataGridView Row into TextBox in Windows Forms Application

Hi...

This is my main form

And above table is my transaction table for above form....

so the query is like...

when i will select the month from datetimepicker as march 2013.. den it should display the

the value of month from respective 3 gridviews  in their respective textbox as shown in above form (for eg:Total donation=10000,monthly expenditure=30,event expenditure=6160)...

Now logic is dat....

monthly donation  + previous balance-monthly expenditure+event expenditure=balance

Nw on selection of month the data should be displayed in textboxes n d previous balance (means balance of feb) should be displayed at that event...

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace ngoo
{
    public partial class Transaction : Form
    {
        public Transaction()
        {
            InitializeComponent();
        }
        SqlConnection con = new SqlConnection("Data Source=ABCD;Initial Catalog=Ngo;Integrated Security=True");
        private void Donations_Load(object sender, EventArgs e)
        {
            dateTimePicker1.CustomFormat = "MMMM yyyy";
            dateTimePicker1.ShowUpDown = true;
            dataGridView3.CellClick += new DataGridViewCellEventHandler(dataGridView3_CellClick);
            dataGridView2.CellClick += new DataGridViewCellEventHandler(dataGridView2_CellClick);
           dataGridView4.CellClick += new DataGridViewCellEventHandler(dataGridView4_CellClick);
            textBox7.ReadOnly = true; 
            try
            {
                DataTable dt = new DataTable();
                DataTable dt1 = new DataTable();
                DataTable dt2 = new DataTable();
                con.Open();
                SqlDataAdapter sda = new SqlDataAdapter("select month(Date) as Month,year(Date) as year,sum(Rupees) as Total from Donors group by month(Date),year(Date)", con);
                SqlDataAdapter sda1 = new SqlDataAdapter("select month(Date) as Month,year(Date) as year,sum(Total) as Total from Des_eve_exp group by month(Date),year(Date)", con);
                SqlDataAdapter sda2 = new SqlDataAdapter("select month(Week) as Month,year(Week) as year,sum(GrandTotal) as Total from Week_Exp group by month(Week),year(Week)", con);
                sda.Fill(dt);
                sda1.Fill(dt1);
                sda2.Fill(dt2);
                dataGridView3.DataSource = dt;
                dataGridView2.DataSource = dt1;
                dataGridView4.DataSource = dt2;
               
            }
            catch (Exception e1)
            {
                MessageBox.Show(e1.Message);
            }
            
            SqlCommand cmd = new SqlCommand("select sum(Rupees) as Rupees  from Donors ", con);
            SqlDataReader rdr1 = cmd.ExecuteReader();
            while (rdr1.Read())
            {
                textBox1.Text = (rdr1["Rupees"].ToString());
            }
            if (rdr1 != null)
                rdr1.Close();


            cmd.ExecuteNonQuery();
            con.Close();

        }

        private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)
        {
            if (e.ColumnIndex == 0)
            {
                textBox7.Text = dataGridView1.Rows[e.RowIndex].Cells[1].Value.ToString();
            }
        }

        private void tabPage2_Click(object sender, EventArgs e)
        {
            con.Open();
            SqlCommand cmd = new SqlCommand("select month(Date) as Month,year(Date) as Year,sum(Rupees) as Total from Donors group by Month(Date),year(Date)", con);
            cmd.ExecuteNonQuery();
            con.Close();
        }

        private void dataGridView3_CellClick(object sender, DataGridViewCellEventArgs e)
        {
            if (e.ColumnIndex == 0)
            {
                string a;
                a = textBox6.Text;
                textBox6.Text = dataGridView3.Rows[e.RowIndex].Cells[2].Value.ToString();
            }
        }

        private void dataGridView2_CellClick(object sender, DataGridViewCellEventArgs e)
        {
            if (e.ColumnIndex == 0)
            {
                textBox5.Text = dataGridView2.Rows[e.RowIndex].Cells[2].Value.ToString();
            }
        }

        private void dataGridView4_CellClick(object sender, DataGridViewCellEventArgs e)
        {
            if (e.ColumnIndex == 0)
            {
                textBox2.Text = dataGridView4.Rows[e.RowIndex].Cells[2].Value.ToString();
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int  a = Convert.ToInt32( textBox6.Text);
            int b = Convert.ToInt32(textBox4.Text);
            int c = a + b;
            int d = Convert.ToInt32(textBox2.Text);
            int e1 = Convert.ToInt32(textBox5.Text);
            int f = d + e1;
            int g = c - f;
            textBox3.Text = g.ToString();
           


        }

        private void dateTimePicker1_ValueChanged(object sender, EventArgs e)
        {
            DateTime selectedDate = dateTimePicker1.Value;
            DateTime lastDayOfMonth = new DateTime(
    	    selectedDate.Year,
            selectedDate.Month,
            DateTime.DaysInMonth(selectedDate.Year, selectedDate.Month)); 

            
             }
        
        }
    }