# __construct 方法 ```php void AsyncUdpConnection::__construct(string $remote_address) ``` 创建一个udp连接对象。 AsyncUdpConnection可以让Workerman作为客户端与远程服务端传输udp数据。 ## 参数 参数:``` remote_address ``` 连接的地址,例如<br> ``` udp://192.168.1.1:1234 ```<br> ``` frame://192.168.1.1:8080 ```<br> ``` text://192.168.1.1:8080 ```<br> ## 示例 ```php use Workerman\Worker; use Workerman\Connection\AsyncUdpConnection; use Workerman\Lib\Timer; $worker = new Worker('udp://0.0.0.0:1234'); $worker->onWorkerStart = function(){ // 1秒后启动一个udp客户端,连接1234端口并发送字符串 hi Timer::add(1, function(){ $udp_connection = new AsyncUdpConnection('udp://127.0.0.1:1234'); $udp_connection->onConnect = function($udp_connection){ $udp_connection->send('hi'); }; $udp_connection->onMessage = function($udp_connection, $data){ // 收到服务端返回的数据 hello echo "recv $data\r\n"; // 关闭连接 $udp_connection->close(); }; $udp_connection->connect(); }, null, false); }; $worker->onMessage = function($connection, $data) { // 收到AsyncUdpConnection客户端发来的数据,返回字符串 hello $connection->send("hello"); }; Worker::runAll(); ``` 执行后打印类似: ``` recv hello ```