解决方法
您不想创建无限循环,但可以设置超时.基本上循环为X秒等待某种数据,如果没有发生,则向客户端发送响应,告诉它需要发起新请求,该请求具有相同的超时时间.
$source; // some data source - db,etc
$data = null; // our return data
$timeout = 30; // timeout in seconds
$now = time(); // start time
// loop for $timeout seconds from $now until we get $data
while((time() - $now) < $timeout) {
// fetch $data
$data = $source->getData();
// if we got $data,break the loop
if (!empty($data)) break;
// wait 1 sec to check for new $data
usleep(10000);
}
// if there is no $data,tell the client to re-request (arbitrary status message)
if (empty($data)) $data = array('status'=>'no-data');
// send $data response to client
echo json_encode($data);
