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php pthreads的使用方法

藏色散人

Sep 15, 2021 am 10:20 AM

phppthreads

php pthreads的使用方法：1、透過「pecl install pthreads」安裝pthreads；2、在需要控制多個執行緒同一時刻只能有一個執行緒工作的情況下使用互斥鎖。

php pthreads的使用方法

本文操作環境：windows7系統、php7.0.2版，DELL G3電腦

php多執行緒pthreads的安裝與使用

安裝Pthreads 基本上需要重新編譯PHP，加上--enable-maintainer-zts 參數，但是用這個文檔很少；bug會很多很有很多意想不到的問題，生成環境上只能呵呵了，所以這個東西玩就算了，真正多執行緒還是用Python、C等等

以下程式碼大部分來自網路

一、安裝

#這裡使用的是 php-7.0.2

./configure \
--prefix=/usr/local/php7 \
--with-config-file-path=/etc \
--with-config-file-scan-dir=/etc/php.d \
--enable-debug \
--enable-maintainer-zts \
--enable-pcntl \
--enable-fpm \
--enable-opcache \
--enable-embed=shared \
--enable-json=shared \
--enable-phpdbg \
--with-curl=shared \
--with-mysql=/usr/local/mysql \
--with-mysqli=/usr/local/mysql/bin/mysql_config \
--with-pdo-mysql


make && make install

安裝pthreads

pecl install pthreads

二、Thread

<?php
#1
$thread = new class extends Thread {
	public function run() {
		echo "Hello World {$this->getThreadId()}\n";                                                                                  
	}   
};

$thread->start() && $thread->join();



#2

class workerThread extends Thread { 
	public function __construct($i){
		$this->i=$i;
	}

	public function run(){
		while(true){
			echo $this->i."\n";
			sleep(1);
		} 
	} 
}

for($i=0;$i<50;$i++){
	$workers[$i]=new workerThread($i);
	$workers[$i]->start();
}

?>

三、 Worker 與Stackable

Stackables are tasks that are executed by Worker threads. You can synchronize with, read, and write Stackable objects before, after and during their execution.

<?php
class SQLQuery extends Stackable {

	public function __construct($sql) {
		$this->sql = $sql;
	}

	public function run() {
		$dbh  = $this->worker->getConnection();
		$row = $dbh->query($this->sql);
		while($member = $row->fetch(PDO::FETCH_ASSOC)){
			print_r($member);
		}
	}

}

class ExampleWorker extends Worker {
	public static $dbh;
	public function __construct($name) {
	}

	public function run(){
		self::$dbh = new PDO(&#39;mysql:host=10.0.0.30;dbname=testdb&#39;,&#39;root&#39;,&#39;123456&#39;);
	}
	public function getConnection(){
		return self::$dbh;
	}
}

$worker = new ExampleWorker("My Worker Thread");

$sql1 = new SQLQuery(&#39;select * from test order by id desc limit 1,5&#39;);
$worker->stack($sql1);

$sql2 = new SQLQuery(&#39;select * from test order by id desc limit 5,5&#39;);
$worker->stack($sql2);

$worker->start();
$worker->shutdown();
?>

<?php
$counter = 0;
$handle=fopen("/tmp/counter.txt", "w");
fwrite($handle, $counter );
fclose($handle);

class CounterThread extends Thread {
	public function __construct($mutex = null){
		$this->mutex = $mutex;
		$this->handle = fopen("/tmp/counter.txt", "w+");
	}
	public function __destruct(){
		fclose($this->handle);
	}
	public function run() {
		if($this->mutex)
			$locked=Mutex::lock($this->mutex);

		$counter = intval(fgets($this->handle));
		$counter++;
		rewind($this->handle);
		fputs($this->handle, $counter );
		printf("Thread #%lu says: %s\n", $this->getThreadId(),$counter);

		if($this->mutex)
			Mutex::unlock($this->mutex);
	}
}

//没有互斥锁
for ($i=0;$i<50;$i++){
	$threads[$i] = new CounterThread();
	$threads[$i]->start();

}

//加入互斥锁
$mutex = Mutex::create(true);
for ($i=0;$i<50;$i++){
	$threads[$i] = new CounterThread($mutex);
	$threads[$i]->start();

}

Mutex::unlock($mutex);
for ($i=0;$i<50;$i++){
	$threads[$i]->join();
}
Mutex::destroy($mutex);

?>

<?php
$tmp = tempnam(__FILE__, &#39;PHP&#39;);
$key = ftok($tmp, &#39;a&#39;);

$shmid = shm_attach($key);
$counter = 0;
shm_put_var( $shmid, 1, $counter );

class CounterThread extends Thread {
	public function __construct($shmid){
		$this->shmid = $shmid;
	}
	public function run() {

		$counter = shm_get_var( $this->shmid, 1 );
		$counter++;
		shm_put_var( $this->shmid, 1, $counter );

		printf("Thread #%lu says: %s\n", $this->getThreadId(),$counter);
	}
}

for ($i=0;$i<100;$i++){
	$threads[] = new CounterThread($shmid);
}
for ($i=0;$i<100;$i++){
	$threads[$i]->start();

}

for ($i=0;$i<100;$i++){
	$threads[$i]->join();
}
shm_remove( $shmid );
shm_detach( $shmid );
?>

互斥鎖什麼

<?php
$tmp = tempnam(__FILE__, &#39;PHP&#39;);
$key = ftok($tmp, &#39;a&#39;);

$shmid = shm_attach($key);
$counter = 0;
shm_put_var( $shmid, 1, $counter );

class CounterThread extends Thread {
	public function __construct($shmid){
		$this->shmid = $shmid;
	}
	public function run() {

		$this->synchronized(function($thread){
				$thread->wait();
				}, $this);

		$counter = shm_get_var( $this->shmid, 1 );
		$counter++;
		shm_put_var( $this->shmid, 1, $counter );

		printf("Thread #%lu says: %s\n", $this->getThreadId(),$counter);
	}
}

for ($i=0;$i<100;$i++){
	$threads[] = new CounterThread($shmid);
}
for ($i=0;$i<100;$i++){
	$threads[$i]->start();

}

for ($i=0;$i<100;$i++){
	$threads[$i]->synchronized(function($thread){
			$thread->notify();
			}, $threads[$i]);
}

for ($i=0;$i<100;$i++){
	$threads[$i]->join();
}
shm_remove( $shmid );
shm_detach( $shmid );
?>

#情況下會用到互斥鎖？在你需要控制多個執行緒同一時刻只能有一個執行緒工作的情況下可以使用。一個簡單的計數器程序，說明有無互斥鎖情況下的不同

<?php
class Update extends Thread {

    public $running = false;
    public $row = array();
    public function __construct($row) {

	$this->row = $row;
        $this->sql = null;
    }

    public function run() {

	if(strlen($this->row[&#39;bankno&#39;]) > 100 ){
		$bankno = safenet_decrypt($this->row[&#39;bankno&#39;]);
	}else{
		$error = sprintf("%s, %s\r\n",$this->row[&#39;id&#39;], $this->row[&#39;bankno&#39;]);
		file_put_contents("bankno_error.log", $error, FILE_APPEND);
	}

	if( strlen($bankno) > 7 ){
		$sql = sprintf("update members set bankno = &#39;%s&#39; where id = &#39;%s&#39;;", $bankno, $this->row[&#39;id&#39;]);

		$this->sql = $sql;
	}

	printf("%s\n",$this->sql);
    }

}

class Pool {
	public $pool = array();
	public function __construct($count) {
		$this->count = $count;
	}
	public function push($row){
		if(count($this->pool) < $this->count){
			$this->pool[] = new Update($row);
			return true;
		}else{
			return false;
		}
	}
	public function start(){
		foreach ( $this->pool as $id => $worker){
			$this->pool[$id]->start();
		}
	}
	public function join(){
		foreach ( $this->pool as $id => $worker){
               $this->pool[$id]->join();
		}
	}
	public function clean(){
		foreach ( $this->pool as $id => $worker){
			if(! $worker->isRunning()){
            	unset($this->pool[$id]);
            }
		}
	}
}

try {
	$dbh    = new PDO("mysql:host=" . str_replace(&#39;:&#39;, &#39;;port=&#39;, $dbhost) . ";dbname=$dbname", $dbuser, $dbpw, array(
		PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
		PDO::MYSQL_ATTR_COMPRESS => true
		)
	);

	$sql  = "select id,bankno from members order by id desc";
	$row = $dbh->query($sql);
	$pool = new Pool(5);
	while($member = $row->fetch(PDO::FETCH_ASSOC))
	{

		while(true){
			if($pool->push($member)){ //压入任务到池中
				break;
			}else{ //如果池已经满，就开始启动线程
				$pool->start();
				$pool->join();
				$pool->clean();
			}
		}
	}
	$pool->start();
    $pool->join();

	$dbh = null;

} catch (Exception $e) {
    echo &#39;[&#39; , date(&#39;H:i:s&#39;) , &#39;]&#39;, &#39;系统错误&#39;, $e->getMessage(), "\n";
}
?>

多線程與共享內存

在共享內存的例子中，沒有使用任何鎖，仍然可能正常工作，可能工作內存操作本身俱備鎖的功能

<?php
class Update extends Thread {

	public $running = false;
	public $row = array();
	public function __construct($row) {

		$this->row = $row;
		$this->sql = null;
		//print_r($this->row);
	}

	public function run() {

		if(strlen($this->row[&#39;bankno&#39;]) > 100 ){
			$bankno = safenet_decrypt($this->row[&#39;bankno&#39;]);
		}else{
			$error = sprintf("%s, %s\r\n",$this->row[&#39;id&#39;], $this->row[&#39;bankno&#39;]);
			file_put_contents("bankno_error.log", $error, FILE_APPEND);
		}

		if( strlen($bankno) > 7 ){
			$sql = sprintf("update members set bankno = &#39;%s&#39; where id = &#39;%s&#39;;", $bankno, $this->row[&#39;id&#39;]);

			$this->sql = $sql;
		}

		printf("%s\n",$this->sql);
	}

}

try {
	$dbh    = new PDO("mysql:host=" . str_replace(&#39;:&#39;, &#39;;port=&#39;, $dbhost) . ";dbname=$dbname", $dbuser, $dbpw, array(
				PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
				PDO::MYSQL_ATTR_COMPRESS => true
				)
			);

	$sql     = "select id,bankno from members order by id desc limit 50";

	$row = $dbh->query($sql);
	$pool = array();
	while($member = $row->fetch(PDO::FETCH_ASSOC))
	{
		$id 	= $member[&#39;id&#39;];
		while (true){
			if(count($pool) < 5){
				$pool[$id] = new Update($member);
				$pool[$id]->start();
				break;
			}else{
				foreach ( $pool as $name => $worker){
					if(! $worker->isRunning()){
						unset($pool[$name]);
					}
				}
			}
		}

	}

	$dbh = null;

} catch (Exception $e) {
	echo &#39;【&#39; , date(&#39;H:i:s&#39;) , &#39;】&#39;, &#39;【系统错误】&#39;, $e->getMessage(), "\n";
}
?>

五、線程同步

有些場景我們不希望thread->start() 就開始運行程序，而是希望線程等待我們的命令。 $thread->wait();測作用是thread->start()後線程並不會立即運行，只有收到$thread->notify(); 發出的信號後才運行

<?php

class WebWorker extends Worker {

	public function __construct(SafeLog $logger) {
		$this->logger = $logger;
	}

	protected $loger;
}

class WebWork extends Stackable {

	public function isComplete() {
		return $this->complete;
	}

	public function run() {
		$this->worker
			->logger
			->log("%s executing in Thread #%lu",
					__CLASS__, $this->worker->getThreadId());
		$this->complete = true;
	}

	protected $complete;
}

class SafeLog extends Stackable {

	protected function log($message, $args = []) {
		$args = func_get_args();

		if (($message = array_shift($args))) {
			echo vsprintf(
					"{$message}\n", $args);
		}
	}
}


$pool = new Pool(8, \WebWorker::class, [new SafeLog()]);

$pool->submit($w=new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->submit(new WebWork());
$pool->shutdown();

$pool->collect(function($work){
		return $work->isComplete();
		});

var_dump($pool);

六、執行緒池

一個Pool類別

<?php

$fp = fopen("/tmp/lock.txt", "r+");
if (flock($fp, LOCK_EX)) {  // 进行排它型锁定
	ftruncate($fp, 0);      // truncate file
	fwrite($fp, "Write something here\n");
	fflush($fp);            // flush output before releasing the lock
	flock($fp, LOCK_UN);    // 释放锁定
} else {
	echo "Couldn&#39;t get the lock!";
}
fclose($fp);



$fp = fopen(&#39;/tmp/lock.txt&#39;, &#39;r+&#39;);
if(!flock($fp, LOCK_EX | LOCK_NB)) {
	echo &#39;Unable to obtain lock&#39;;
	exit(-1);
}
fclose($fp);
?>

動態佇列執行緒池

上面的範例是當執行緒池滿後執行start統一啟動，下面的例子是只要線程池中有空閒便立即建立新線程。

<?php
class Work extends Stackable {

        public function __construct() {
        }

        public function run() {
                $dbh  = $this->worker->getConnection();
                $sql     = "select id,name from members order by id desc limit 50";
                $row = $dbh->query($sql);
                while($member = $row->fetch(PDO::FETCH_ASSOC)){
                        print_r($member);
                }
        }

}

class ExampleWorker extends Worker {
        public static $dbh;
        public function __construct($name) {
        }

        /*
        * The run method should just prepare the environment for the work that is coming ...
        */
        public function run(){
                self::$dbh = new PDO(&#39;mysql:host=192.168.2.1;dbname=example&#39;,&#39;www&#39;,&#39;123456&#39;);
        }
        public function getConnection(){
                return self::$dbh;
        }
}

$worker = new ExampleWorker("My Worker Thread");

$work=new Work();
$worker->stack($work);

$worker->start();
$worker->shutdown();
?>

pthreads Pool類別

# cat pool.php
<?php
class ExampleWorker extends Worker {

	public function __construct(Logging $logger) {
		$this->logger = $logger;
	}

	protected $logger;
}

/* the collectable class implements machinery for Pool::collect */
class Work extends Stackable {
	public function __construct($number) {
		$this->number = $number;
	}
	public function run() {
                $dbhost = &#39;db.example.com&#39;;               // 数据库服务器
                $dbuser = &#39;example.com&#39;;                 // 数据库用户名
                $dbpw = &#39;password&#39;;                               // 数据库密码
                $dbname = &#39;example_real&#39;;
		$dbh  = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
                        PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
                        PDO::MYSQL_ATTR_COMPRESS => true,
			PDO::ATTR_PERSISTENT => true
                        )
                );
		$sql = "select OPEN_TIME, `COMMENT` from MT4_TRADES where LOGIN=&#39;".$this->number[&#39;name&#39;]."&#39; and CMD=&#39;6&#39; and `COMMENT` = &#39;".$this->number[&#39;order&#39;].":DEPOSIT&#39;";
		#echo $sql;
		$row = $dbh->query($sql);
		$mt4_trades  = $row->fetch(PDO::FETCH_ASSOC);
		if($mt4_trades){

			$row = null;

			$sql = "UPDATE db_example.accounts SET paystatus=&#39;成功&#39;, deposit_time=&#39;".$mt4_trades[&#39;OPEN_TIME&#39;]."&#39; where `order` = &#39;".$this->number[&#39;order&#39;]."&#39;;";
			$dbh->query($sql);
			#printf("%s\n",$sql);
		}
		$dbh = null;
		printf("runtime: %s, %s, %s\n", date(&#39;Y-m-d H:i:s&#39;), $this->worker->getThreadId() ,$this->number[&#39;order&#39;]);

	}
}

class Logging extends Stackable {
	protected  static $dbh;
	public function __construct() {
		$dbhost = &#39;db.example.com&#39;;			// 数据库服务器
	        $dbuser = &#39;example.com&#39;;                 // 数据库用户名
        	$dbpw = &#39;password&#39;;                               // 数据库密码
		$dbname = &#39;example_real&#39;;			// 数据库名

		self::$dbh  = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
			PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
			PDO::MYSQL_ATTR_COMPRESS => true
			)
		);

	}
	protected function log($message, $args = []) {
		$args = func_get_args();

		if (($message = array_shift($args))) {
			echo vsprintf("{$message}\n", $args);
		}
	}

	protected function getConnection(){
                return self::$dbh;
        }
}

$pool = new Pool(200, \ExampleWorker::class, [new Logging()]);

$dbhost = &#39;db.example.com&#39;;                      // 数据库服务器
$dbuser = &#39;example.com&#39;;                 // 数据库用户名
$dbpw = &#39;password&#39;;                               // 数据库密码
$dbname = &#39;db_example&#39;;
$dbh    = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
                        PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
                        PDO::MYSQL_ATTR_COMPRESS => true
                        )
                );
$sql = "select `order`,name from accounts where deposit_time is null order by id desc";

$row = $dbh->query($sql);
while($account = $row->fetch(PDO::FETCH_ASSOC))
{
        $pool->submit(new Work($account));
}

$pool->shutdown();

?>

七、多執行緒檔案安全讀寫

LOCK_SH 取得共享鎖定（讀取的程式）
LOCK_EX 取得獨佔鎖定（寫入的程式
#LOCK_UN 釋放鎖定（無論共用或獨佔）
#LOCK_NB 如果不希望flock() 在鎖定時堵塞

<?php
class ExampleWorker extends Worker {

	#public function __construct(Logging $logger) {
	#	$this->logger = $logger;
	#}

	#protected $logger;
	protected  static $dbh;
	public function __construct() {

	}
	public function run(){
		$dbhost = &#39;db.example.com&#39;;			// 数据库服务器
	    $dbuser = &#39;example.com&#39;;        	// 数据库用户名
        $dbpw = &#39;password&#39;;             	// 数据库密码
		$dbname = &#39;example&#39;;				// 数据库名

		self::$dbh  = new PDO("mysql:host=$dbhost;port=3306;dbname=$dbname", $dbuser, $dbpw, array(
			PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
			PDO::MYSQL_ATTR_COMPRESS => true,
			PDO::ATTR_PERSISTENT => true
			)
		);

	}
	protected function getInstance(){
        return self::$dbh;
    }

}

/* the collectable class implements machinery for Pool::collect */
class Work extends Stackable {
	public function __construct($data) {
		$this->data = $data;
		#print_r($data);
	}

	public function run() {
		#$this->worker->logger->log("%s executing in Thread #%lu", __CLASS__, $this->worker->getThreadId() );

		try {
			$dbh  = $this->worker->getInstance();
			#print_r($dbh);
               		$id = $this->data[&#39;id&#39;];
			$mobile = safenet_decrypt($this->data[&#39;mobile&#39;]);
			#printf("%d, %s \n", $id, $mobile);
			if(strlen($mobile) > 11){
				$mobile = substr($mobile, -11);
			}
			if($mobile == &#39;null&#39;){
			#	$sql = "UPDATE members_digest SET mobile = &#39;".$mobile."&#39; where id = &#39;".$id."&#39;";
			#	printf("%s\n",$sql);
			#	$dbh->query($sql);
				$mobile = &#39;&#39;;
				$sql = "UPDATE members_digest SET mobile = :mobile where id = :id";
			}else{
				$sql = "UPDATE members_digest SET mobile = md5(:mobile) where id = :id";
			}
			$sth = $dbh->prepare($sql);
			$sth->bindValue(&#39;:mobile&#39;, $mobile);
			$sth->bindValue(&#39;:id&#39;, $id);
			$sth->execute();
			#echo $sth->debugDumpParams();
		}
		catch(PDOException $e) {
			$error = sprintf("%s,%s\n", $mobile, $id );
			file_put_contents("mobile_error.log", $error, FILE_APPEND);
		}

		#$dbh = null;
		printf("runtime: %s, %s, %s, %s\n", date(&#39;Y-m-d H:i:s&#39;), $this->worker->getThreadId() ,$mobile, $id);
		#printf("runtime: %s, %s\n", date(&#39;Y-m-d H:i:s&#39;), $this->number);
	}
}

$pool = new Pool(100, \ExampleWorker::class, []);

#foreach (range(0, 100) as $number) {
#	$pool->submit(new Work($number));
#}

$dbhost = &#39;db.example.com&#39;;                     // 数据库服务器
$dbuser = &#39;example.com&#39;;                 		// 数据库用户名
$dbpw = &#39;password&#39;;                             // 数据库密码
$dbname = &#39;example&#39;;
$dbh    = new PDO("mysql:host=$dbhost;port=3307;dbname=$dbname", $dbuser, $dbpw, array(
                        PDO::MYSQL_ATTR_INIT_COMMAND => &#39;SET NAMES \&#39;UTF8\&#39;&#39;,
                        PDO::MYSQL_ATTR_COMPRESS => true
                        )
                );
#print_r($dbh);

#$sql = "select id, mobile from members where id < :id";
#$sth = $dbh->prepare($sql);
#$sth->bindValue(&#39;:id&#39;,300);
#$sth->execute();
#$result = $sth->fetchAll();
#print_r($result);
#
#$sql = "UPDATE members_digest SET mobile = :mobile where id = :id";
#$sth = $dbh->prepare($sql);
#$sth->bindValue(&#39;:mobile&#39;, &#39;aa&#39;);
#$sth->bindValue(&#39;:id&#39;,&#39;272&#39;);
#echo $sth->execute();
#echo $sth->queryString;
#echo $sth->debugDumpParams();


$sql = "select id, mobile from members order by id asc"; // limit 1000";
$row = $dbh->query($sql);
while($members = $row->fetch(PDO::FETCH_ASSOC))
{
        #$order =  $account[&#39;order&#39;];
        #printf("%s\n",$order);
        //print_r($members);
        $pool->submit(new Work($members));
		#unset($account[&#39;order&#39;]);
}

$pool->shutdown();

?>

八、多執行緒與資料連線

pthreads 與pdo 同時使用是，需要注意一點，需要靜態宣告public static $dbh;並且透過單一範例模式存取資料庫連線。

Worker 與PDO

<?php
$dbh = new PDO(&#39;mysql:host=localhost;dbname=test&#39;, $user, $pass, array(
    PDO::ATTR_PERSISTENT => true
));
?>

Pool 與PDO

在執行緒池中連結資料庫

rrreee

進一步改進上面程序，我們使用單例模式$this->worker->getInstance(); 全局僅做一次資料庫連接，線程使用共享的資料庫連接

rrreee

多線程中操作資料庫總結

總的來說pthreads 仍然處在發展中，仍有一些不足的地方，我們也可以看到pthreads的git不斷改進這個專案

資料庫持久連結很重要，否則每個線程都會開啟一次資料庫連接，然後關閉，會導致很多鏈接超時。

rrreee推薦學習：《PHP視頻教程

》###

以上是php pthreads的使用方法的詳細內容。更多資訊請關注PHP中文網其他相關文章！

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一、安裝

二、Thread

三、 Worker 與Stackable

<?php $dbh = new PDO(&#39;mysql:host=localhost;dbname=test&#39;, $user, $pass, array( PDO::ATTR_PERSISTENT => true )); ?>

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VSCode Windows 64位元 下載

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SublimeText3 Mac版

熱門話題

<?php $dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass, array( PDO::ATTR_PERSISTENT => true )); ?>

VSCode Windows 64位元下載