private void btn_send_Click(object sender, EventArgs e)
{
string from = tb_from.Text.Trim();
string to = tb_to.Text.Trim();
string content = tb_content.Text;
Msg msg = new Msg(from, to, content);
MyIMClient.SendMsg(msg);
builder.AppendFormat("{0} {1}", msg.Time, msg.From).AppendLine();
builder.AppendLine(msg.Content);
builder.AppendLine();
tb_received.Text = builder.ToString();;
}
