//Going to exam management form when click on exam management button form dashboard
private void collectivedash_Click(object sender, EventArgs e)
{
CollectiveInformation collinf = new CollectiveInformation();
this.Hide();
collinf.ShowDialog();
}
//Back button
private void button4_Click(object sender, EventArgs e)
{
CollectiveInformation coli = new CollectiveInformation();
this.Hide();
coli.ShowDialog();
}