private void btn_sendmsg_Click(object sender, EventArgs e)
{
if (app != null && app.State == SuperSocket.SocketBase.ServerState.Running && txt_msg.Text.Length > 0)
{
foreach (var item in app.GetAllSessions())
{
new CMD_0004_DownText().Push(item, txt_msg.Text);
}
txt_msg.Text = "";
}
}