C#

private void Form1_Load(object sender, EventArgs e)
{
    string cifTime = timeCIF.Text;
    string chkCIF = "N";
    emailBody.Text = "Example\nCIF = " + chkCIF + "\nTIME = " + timeCIF.Text;
}

private void updateButton_Click(object sender, EventArgs e)
{
    //There is a combo box on this form and example is the first option
    if (comboInst.Text == "Example")
    {
        //Here is where the check box verification is, if it is true it should change the N to Y
        if (checkCIF.Checked == true)
        {
            //This part needs to update the current contents of the email body. Obviously, this isn't working for me so I commented out some examples I tried...
            //string s = emailBody.Text;
            //string chkCIF = "Y";

            //s = s.Replace("N", chkCIF);

            string theString = emailBody.Text;
            theString.Remove(3, 2).Insert(3, "Y");
        }
    }

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;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        powerdbDataSet db = new powerdbDataSet();
        private void Form1_Load(object sender, EventArgs e)
        {

            // TODO: This line of code loads data into the 'powerdbDataSet.powertable' table. You can move, or remove it, as needed.
            this.powertableTableAdapter.Fill(this.powerdbDataSet.powertable);
            chart1.Series[0].XValueMember = "time";
            chart1.Series[0].YValueMembers ="power";
            powertableBindingSource.DataSource = db.powertable;


        }

        private void chart1_Click(object sender, EventArgs e)
        {

        }
    }
}