private void addNewBooksToolStripMenuItem_Click(object sender, EventArgs e)
{
this.IsMdiContainer = true;
FormAddBook addBookForm = new FormAddBook();
addBookForm.MdiParent = this;
addBookForm.Show();
}
private void button5_Click(object sender, EventArgs e)
{
FormAddBook addbook = new FormAddBook();
addbook.Show();
}