【公司面试题之：腾讯 PHP 工程师笔试题】1． 请对 POSIX 风格和兼容 Perl 风格两种正则表达式的主要函数进行类比说明 ereg preg_match ereg_replace preg_replace 2． 请说明在 php.ini 中 safe_mode 开启之后对于 PHP 系统函数的影响 3． PHP5 中魔术方法函数有哪几个，请举例说明各自的用法 __sleep __wakeup __toString __set_state __construct, __destruct __call, __get, __set, __isset, __unset __sleep, __wakeup, __toString, __set_state, __clone __autoload 4． 请写出让，并说明如何在命令行下运行 PHP 脚本（写出两种方式）同时向 PHP 脚本传递参数？ 5． PHP 的垃圾收集机制是怎样的 6．使对象可以像数组一样进行 foreach 循环，要求属性必须是私有。 (Iterator 模式的 PHP5 实现，写一类实现 Iterator 接口) 7．请写一段 PHP 代码，确保多个进程同时写入同一个文件成功 8． 用 PHP 实现一个双向队列 9． 使用正则表达式提取一段标识语言（html 或 xml）代码段中指定标签的指定属性值（需考虑属性值对不规则的情况，如大小写不敏感，属性名值与等号间有空格等）。此处假设需提取 test 标签的attr 属性值，请自行构建包含该标签的串 <test attr=”ddd”> <test attr\s*=\s*[“ ¦’](.*?)[” ¦’].*?> 10．请使用 socket 相关函数（非 curl）实现如下功能：构造一个 post 请求，发送到指定 http server的指定端口的指定请求路径（如 http://www. exam ple.com:8080/test ）。请求中包含以下变量： 用户名（username）：温柔一刀 密码（pwd）：&123=321&321=123& 个人简介（intro）：Hello world! 且该 http server 需要以下 cookie 来进行简单的用户动作跟踪： cur_query：you&me last_tm：...（上次请求的 unix 时间戳，定为当前请求时间前 10 分钟） cur_tm：...（当前请求的 unix 时间戳） 设置超时为 10 秒，发出请求后，将 http server 的响应内容输出。 复制内容到剪贴板 代码:Function encode($data, $sep = ‘&’){ while (list($k,$v) = each($data)) { $encoded .= ($encoded ? "$sep" : ""); $encoded .= rawurlencode($k)."=".rawurlencode($v); } Return $encoded; } Function post($url, $post, $cookie){ $url = parse_url($url); $post = encode($data, ‘&’); $cookie = encode($cookieArray, ‘;’); $fp = fsockopen($url['host'], $url['port'] ? $url['port'] : 80, $errno, $errstr, 10); if (!$fp) return "Failed to open socket to $url[host]"; fputs($fp, sprintf("POST %s%s%s HTTP/1.0\n", $url['path'], $url['query'] ? "?" : "", $url['query'])); fputs($fp, "Host: $url[host]\n"); fputs($fp, "Content-type: application/x-www-form-urlencoded\n"); fputs($fp, "Content-length: " . strlen($encoded) . "\n"); fputs($fp, "Cookie: $cookie\n\n"); fputs($fp, "Connection: close\n\n"); fputs($fp, "$post \n"); while (!feof($fp)) { echo fgets($fp, 128); } fclose($fp); } $url = ‘[url]http://www.example.com:8080/test[/url]’; $encoded = username=温柔一刀& pwd= $post = array( ‘username’=> ‘温柔一刀’, ‘pwd => ‘&123=321&321=123&’, ‘intro => ‘Hello world!’ ); $cookie = array( ‘cur_query’ => ‘you&me, ‘last_tm’ => time() - 600, ‘cur_tm ‘=> time() ); Post($url, $post, $cookie); 11．你用什么方法检查 PHP 脚本的执行效率（通常是脚本执行时间）和数据库 SQL 的效率（通常是数据库 Query 时间），并定位和分析脚本执行和数据库查询的瓶颈所在？ 1．脚本执行时间，启用 xdebug，使用 WinCacheGrind 分析。 2．数据库查询，mysql 使用 EXPLAIN 分析查询，启用 slow query log 记录慢查询。 PHP LAMP Engineer Test Paper Question 1 What does <? echo count ("123") ?> print out? A) 3 B) False C) Null D) 1 E) 0 Question 2 Which of the following snippets prints a representation of 42 with two decimal places? A) printf("%.2d\n", 42); B) printf("%1.2f\n", 42); C) printf("%1.2u\n", 42); Question 3 Given $text = 'Content-Type: text/xml'; Which of the following prints 'text/xml'? A) print substr($text, strchr($text, ':')); B) print substr($text, strchr($text, ':') + 1); C) print substr($text, strpos($text, ':') + 1); D) print substr($text, strpos($text, ':') + 2); E) print substr($text, 0, strchr($text, ':') Question 4 What is the value of $a? <?php $a = in_array('01', array('1')) == var_dump('01' == 1); ?> A) True B) False Question 5 What is the value of $result in the following PHP code? <?php function timesTwo($int) { $int = $int * 2; } $int = 2; $result = timesTwo($int); ?>; Answer: NULL Question 6 The code below ___________ because ____________. <?php class Foo { ?> <?php function bar() { print "bar"; } } ?> A) will work, class definitions can be split up into multiple PHP blocks. B) will not work, class definitions must be in a single PHP block. C) will not work, class definitions must be in a single file but can be in multiple PHP blocks. D) will work, class definitions can be split up into multiple files and multiple PHP blocks. Question 7 When turned on, ____________ will _________ your script with different variables from HTML forms and cookies. A) show_errors, enable B) show_errors, show C) register_globals, enhance D) register_globals, inject Question 8 What will be the output of the following PHP code: <?php echo count(strlen("http://php.net")); ?> Answer: 1 Question 9 What is the best all-purpose way of comparing two strings? A) Using the strpos function B) Using the == operator C) Using strcasecmp() D) Using strcmp() Question 10 What is the difference between "print()" and "echo()"? Answer: print is a function,echo is a language construct