private void agregarClienteToolStripMenuItem_Click(object sender, EventArgs e)
{
if (client == null)
{
client = new frmAgregarClientes();
client.MdiParent = this;
client.FormClosed += new FormClosedEventHandler(client_FormClosed);
client.Show();
}
}
void client_FormClosed(object sender, EventArgs e)
{
client = null;
}