private void inDanhSáchThuLệPhíToolStripMenuItem_Click(object sender, EventArgs e)
{
if (!CheckExitsFrom("FrmDsThuLePhi"))
{
FrmDsThuLePhi fm = new FrmDsThuLePhi();
fm.MdiParent = this;
fm.Show();
}
else ActiveChildForm("FrmDsThuLePhi");
}
private void button4_Click(object sender, EventArgs e)
{
FrmDsThuLePhi f = new FrmDsThuLePhi();
f.Show();
}