php实现udp通信

PHP实现UDP通信的方法

创建UDP服务器端

使用stream_socket_server函数创建UDP服务器：

$server = stream_socket_server("udp://0.0.0.0:9999", $errno, $errstr, STREAM_SERVER_BIND);
if (!$server) {
    die("Error: $errstr ($errno)");
}

while (true) {
    $data = stream_socket_recvfrom($server, 1024, 0, $peer);
    echo "Received: $data from $peer\n";
    stream_socket_sendto($server, "Server received: $data", 0, $peer);
}

创建UDP客户端

使用stream_socket_client函数创建UDP客户端：

$client = stream_socket_client("udp://127.0.0.1:9999", $errno, $errstr);
if (!$client) {
    die("Error: $errstr ($errno)");
}

stream_socket_sendto($client, "Hello UDP Server", 0);
$response = stream_socket_recvfrom($client, 1024, 0, $peer);
echo "Response: $response from $peer\n";

使用socket扩展实现

创建UDP服务器：

$socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
socket_bind($socket, '0.0.0.0', 9999);

while (true) {
    socket_recvfrom($socket, $buf, 1024, 0, $ip, $port);
    echo "Received $buf from $ip:$port\n";
    socket_sendto($socket, "ACK: $buf", strlen("ACK: $buf"), 0, $ip, $port);
}

创建UDP客户端：

$sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
$msg = "Hello UDP Server";
$len = strlen($msg);
socket_sendto($sock, $msg, $len, 0, '127.0.0.1', 9999);
socket_recvfrom($sock, $buf, 1024, 0, $server, $port);
echo "Received $buf from $server:$port\n";

注意事项

UDP是无连接的协议，不需要建立连接即可发送数据 UDP不保证数据包的顺序和可靠性 适合对实时性要求高但允许少量丢包的应用场景 最大传输单元(MTU)通常限制在1500字节左右