private void checkBox1_Click(object sender, System.EventArgs e)
{
if (checkBox1.Checked==true)
{
textBox1.ReadOnly = false;
textBox2.ReadOnly = false;
textBox3.ReadOnly = false;
textBox1.Text = "";
textBox2.Text = "";
textBox3.Text = "";
}
else if (checkBox1.Checked==false)
{
textBox1.ReadOnly = true;
textBox2.ReadOnly = true;
textBox3.ReadOnly = true;
}
}