private void broadCastButton_Click(object sender, EventArgs e) { if (isPhysician) { foreach (User u in users) { network.sendChatMessage(TChatSend.Text, username, u.username); } RTBChatText.Text += "BROADCAST: " + username + ": " + TChatSend.Text + System.Environment.NewLine; } else { MessageBox.Show("cliënten kunnen geen broadcastbericht versturen!"); } RTBChatText.Text += username + ": " + TChatSend.Text + System.Environment.NewLine; }