how to make this code work .. i want to show leftdays

Question

SqlConnection myconnection = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=c:\documents and settings\muhammad\my documents\visual studio 2010\Projects\ProjectClock\ProjectClock\ClockDB.mdf;Integrated Security=True;User Instance=True");

private void button1_Click(object sender, EventArgs e)

{

myconnection.Open();

SqlCommand cmd = new SqlCommand();

cmd.CommandType = CommandType.Text;

cmd.CommandText = "insert into employTable(employname,ismarred,salarydate,expiredate) values('" + textBox1.Text + "','" + checkBox1.Checked + "','" + dateTimePicker1.Value.ToString("M/d/yyyy") + "','" + dateTimePicker1.Value.AddDays(365).ToString("M/d/yyyy") + "')";

cmd.Connection = myconnection;

cmd.ExecuteNonQuery();

string selectSql = "select * from employTable";

SqlCommand com = new SqlCommand(selectSql, myconnection);

string first;

string Second;

DateTime salaryDate;

DateTime expireDate;

int daysleft;

 

 

////////////////this block of code is not showing the messagebox it dont't gives error /////////////////////////// 

using (SqlDataReader read = cmd.ExecuteReader())

{

while (read.Read())

{

first = (read["salarydate"].ToString());

Second = (read["expiredate"].ToString());

salaryDate = DateTime.ParseExact(first, "MM/dd/yyyy", System.Globalization.CultureInfo.InvariantCulture);

expireDate = DateTime.ParseExact(Second, "MM/dd/yyyy", System.Globalization.CultureInfo.InvariantCulture);

TimeSpan t1 = expireDate - salaryDate;

daysleft = t1.Days;

MessageBox.Show(daysleft.ToString(), "Days Left");

}

/===================/

}

myconnection.Close();

}

}