/// <summary>
/// 连接服务器并按标题订阅内容
/// </summary>
/// <param name="e"></param>
/// <returns></returns>
private static async Task Connected(MqttClientConnectedEventArgs e)
{
try
{
List <TopicFilter> listTopic = new List <TopicFilter>();
if (listTopic.Count() <= 0)
{
var topicFilterBulder = new TopicFilterBuilder().WithTopic(Topic).Build();
listTopic.Add(topicFilterBulder);
Console.WriteLine("Connected >>Subscribe " + Topic);
}
await mqttClient.SubscribeAsync(listTopic.ToArray());
Console.WriteLine("Connected >>Subscribe Success");
}
catch (Exception exp)
{
Console.WriteLine(exp.Message);
}
}
private void BtnSubscribe_Click(object sender, RoutedEventArgs e)
{
string topic = txtSubTopic.Text.Trim();
if (string.IsNullOrEmpty(topic))
{
MessageBox.Show("订阅主题不能为空！");
return;
}
if (!mqttClient.IsConnected)
{
MessageBox.Show("MQTT客户端尚未连接！");
return;
}
mqttClient.SubscribeAsync(new List <TopicFilter> {
new TopicFilter(topic, MqttQualityOfServiceLevel.AtMostOnce)
});
txtReceiveMessage.AppendText($"已订阅[{topic}]主题" + Environment.NewLine);
txtSubTopic.IsEnabled = false;
btnSubscribe.IsEnabled = false;
}