запутался

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

private void textBox1_TextChanged(object sender, EventArgs e)
{
int a;
a = Convert.ToInt16(textBox1.Text);

}

private void textBox2_TextChanged(object sender, EventArgs e)
{
int b;
b = Convert.ToInt16(textBox2.Text);
}

private void textBox4_TextChanged(object sender, EventArgs e)
{
int c;
c = Convert.ToInt16(textBox4.Text);
}

private void textBox3_TextChanged(object sender, EventArgs e)
{
int f;
f = Convert.ToInt16(textBox3.Text);
}

private void textBox5_TextChanged(object sender, EventArgs e)
{
int g;
g = Convert.ToInt16(textBox5.Text);
}

private void button1_Click(object sender, EventArgs e);
????????????????????????
}