php中foreach跟for到底有没有区别，尤其是在处理多线程（本例是对IOS进行推送）方面

php中foreach和for到底有没有区别，尤其是在处理多线程（本例是对IOS进行推送）方面？
遇到一个困难，解决了好长时间，最后发现是用for 不好使，用foreach好使。

<br /><?php<br /> // 循环有问题<br />require_once "/home/bae/app/include/db.php";<br /> <br />$db_obj = new DB();<br />$sql = "select appleID from appleDevice ";<br />$result = $db_obj->db_array($sql);<br /><br />print_r("the array is:".$result);<br /><br />var_dump($result);<br /> <br />$countArray = count($result); <br /> <br />print_r("number:".$countArray);<br /><br /><br />	$passphrase = 'zhaojian';<br />	$message = 'My first push notification!';<br />	 <br />	$ctx = stream_context_create();<br />	stream_context_set_option($ctx, 'ssl', 'local_cert', 'ck.pem');<br />	stream_context_set_option($ctx, 'ssl', 'passphrase', $passphrase);<br />	 <br />	// Open a connection to the APNS server<br />	$fp = stream_socket_client(<br />	    'ssl://gateway.sandbox.push.apple.com:2195', $err,<br />	    $errstr, 60, STREAM_CLIENT_CONNECT|STREAM_CLIENT_PERSISTENT, $ctx);<br />	 <br />	if (!$fp)<br />	    exit("Failed to connect: $err $errstr" . PHP_EOL);<br />	 <br />	echo 'Connected to APNS' . PHP_EOL;<br /><br />	// Create the payload body<br />	$body['aps'] = array(<br />	    'alert' => $message,<br />	    'sound' => 'default'<br />	    );<br />	 <br />	// Encode the payload as JSON<br />	$payload = json_encode($body);<br /> <br /> 	//$result = array("2d4401e324e7bd0ce574508b0849c7584b965df4ab183c82b3da65855835ec27","e20f2879b0ff6b7c6554b44f339c9e4bade2ee4a5a3a6d5de77bda074269221f");<br />	<br />	foreach ($result as $device) {<br />	$deviceToken = $device['appleID'];<br />	 <br /><br />	print_r("the ".$i." item :".$deviceToken);<br /><br />	$msg = chr(0) . pack('n', 32) . pack('H*', $deviceToken) . pack('n', strlen($payload)) . $payload;<br />	$result = fwrite($fp, $msg, strlen($msg));<br /><br />	if (!$result)<br />	    echo 'Message not delivered' . PHP_EOL;<br />	else<br />	    echo 'Message successfully delivered' . PHP_EOL;<br />} <br />	 <br />	 <br />	fclose($fp);   <br /><br />?><br /><br /><br /><br />

这段代码是针对php对IOS推送的代码。
用foreach那里，如果改成for i=0 i

------解决方案--------------------
没有看到你的 for 循环的写法
但你的 foreach 中有
foreach ($result as $device) {
  $result = fwrite($fp, $msg, strlen($msg));
改变了原始量
如果 for 循环也是这样的话，自然就不行了

foreach 是对数组的引用进行循环的