必须收藏的23个php实用代码片段

在编写代码的时候有个神奇的工具总是好的！下面这里收集了 40+ PHP 代码片段，可以帮助你开发 PHP 项目。
这些 PHP 片段对于 PHP 初学者也非常有帮助，非常容易学习，让我们开始学习吧～
1. 发送 SMS
在开发 Web 或者移动应用的时候，经常会遇到需要发送 SMS 给用户，或者因为登录原因，或者是为了发送信息。下面的 PHP 代码就实现了发送 SMS 的功能。
为了使用任何的语言发送 SMS，需要一个 SMS gateway。大部分的 SMS 会提供一个 API，这里是使用 MSG91 作为 SMS gateway。

    function send_sms($mobile,$msg)
    {
    $authKey = "XXXXXXXXXXX";
    date_default_timezone_set("Asia/Kolkata");
    $date = strftime("%Y-%m-%d %H:%M:%S");
    //Multiple mobiles numbers separated by comma
    $mobileNumber = $mobile;

    //Sender ID,While using route4 sender id should be 6 characters long.
    $senderId = "IKOONK";

    //Your message to send, Add URL encoding here.
    $message = urlencode($msg);

    //Define route
    $route = "template";
    //Prepare you post parameters
    $postData = array(
      'authkey' => $authKey,
      'mobiles' => $mobileNumber,
      'message' => $message,
      'sender' => $senderId,
      'route' => $route
    );

    //API URL
    $url="https://control.msg91.com/sendhttp.php";

    // init the resource
    $ch = curl_init();
    curl_setopt_array($ch, array(
      CURLOPT_URL => $url,
      CURLOPT_RETURNTRANSFER => true,
      CURLOPT_POST => true,
      CURLOPT_POSTFIELDS => $postData
      //,CURLOPT_FOLLOWLOCATION => true
    ));


    //Ignore SSL certificate verification
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);


    //get response
    $output = curl_exec($ch);
    //Print error if any
    if(curl_errno($ch))
    {
      echo 'error:' . curl_error($ch);
    }

    curl_close($ch);
    }

其中"$authKey = "XXXXXXXXXXX";"需要你输入你的密码，"$senderId = "IKOONK";"需要你输入你的 SenderID。当输入移动号码的时候需要指定国家代码 (比如，美国是 1，印度是 91 )。
语法：

    <?php
    $message = "Hello World";
    $mobile = "918112998787";
    send_sms($mobile,$message);
    ?>

2. 使用 mandrill 发送邮件
Mandrill 是一款强大的 SMTP 提供器。开发者倾向于使用一个第三方 SMTP provider 来获取更好的收件交付。
下面的函数中，你需要把 "Mandrill.php" 放在同一个文件夹，作为 PHP 文件，这样就可以使用TA来发送邮件。

    function send_email($to_email,$subject,$message1)
    {
    require_once 'Mandrill.php';
    $apikey = 'XXXXXXXXXX'; //specify your api key here
    $mandrill = new Mandrill($apikey);

    $message = new stdClass();
    $message->html = $message1;
    $message->text = $message1;
    $message->subject = $subject;
    $message->from_email = "blog@koonk.com";//Sender Email
    $message->from_name = "KOONK";//Sender Name
    $message->to = array(array("email" => $to_email));
    $message->track_opens = true;

    $response = $mandrill->messages->send($message);
    }

$apikey = 'XXXXXXXXXX'; //specify your api key here"这里需要你指定你的 API 密钥（从 Mandrill 账户中获得）。
语法：

    <?php
    $to = "abc@example.com";
    $subject = "This is a test email";
    $message = "Hello World!";
    send_email($to,$subject,$message);
    ?>

为了达到最好的效果，最好按照 Mandrill 的教程去配置 DNS。

3. PHP 函数：阻止 SQL 注入
SQL 注入或者 SQLi 常见的攻击网站的手段，使用下面的代码可以帮助你防止这些工具。

    function clean($input)
    {
      if (is_array($input))
      {
        foreach ($input as $key => $val)
         {
          $output[$key] = clean($val);
          // $output[$key] = $this->clean($val);
        }
      }
      else
      {
        $output = (string) $input;
        // if magic quotes is on then use strip slashes
        if (get_magic_quotes_gpc())
        {
          $output = stripslashes($output);
        }
        // $output = strip_tags($output);
        $output = htmlentities($output, ENT_QUOTES, 'UTF-8');
      }
    // return the clean text
      return $output;
    }

语法：

    <?php
    $text = "<script>alert(1)</script>";
    $text = clean($text);
    echo $text;
    ?>

4. 检测用户位置
使用下面的函数，可以检测用户是在哪个城市访问你的网站

    function detect_city($ip) {

        $default = 'UNKNOWN';

        $curlopt_useragent = 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2) Gecko/20100115 Firefox/3.6 (.NET CLR 3.5.30729)';

        $url = 'http://ipinfodb.com/ip_locator.php?ip=' . urlencode($ip);
        $ch = curl_init();

        $curl_opt = array(
          CURLOPT_FOLLOWLOCATION => 1,
          CURLOPT_HEADER   => 0,
          CURLOPT_RETURNTRANSFER => 1,
          CURLOPT_USERAGENT  => $curlopt_useragent,
          CURLOPT_URL    => $url,
          CURLOPT_TIMEOUT     => 1,
          CURLOPT_REFERER     => 'http://' . $_SERVER['HTTP_HOST'],
        );

        curl_setopt_array($ch, $curl_opt);

        $content = curl_exec($ch);

        if (!is_null($curl_info)) {
          $curl_info = curl_getinfo($ch);
        }

        curl_close($ch);

        if ( preg_match('{<li>City : ([^<]*)</li>}i', $content, $regs) ) {
          $city = $regs[1];
        }
        if ( preg_match('{<li>State/Province : ([^<]*)</li>}i', $content, $regs) ) {
          $state = $regs[1];
        }

        if( $city!='' && $state!='' ){
         $location = $city . ', ' . $state;
         return $location;
        }else{
         return $default;
        }

      }

语法：

    <?php
    $ip = $_SERVER['REMOTE_ADDR'];
    $city = detect_city($ip);
    echo $city;
    ?>

5. 获取 Web 页面的源代码
使用下面的函数，可以获取任意 Web 页面的 HTML 代码

    function display_sourcecode($url)
    {
    $lines = file($url);
    $output = "";
    foreach ($lines as $line_num => $line) {
      // loop thru each line and prepend line numbers
      $output.= "Line #<b>{$line_num}</b> : " . htmlspecialchars($line) . "\n";
    }
    }

语法：

    <?php
    $url = "http://blog.koonk.com";
    $source = display_sourcecode($url);
    echo $source;
    ?>

6. 计算喜欢你的 Facebook 页面的用户

    function fb_fan_count($facebook_name)
    {
      $data = json_decode(file_get_contents("https://graph.facebook.com/".$facebook_name));
      $likes = $data->likes;
      return $likes;
    }

语法：

    <?php
    $page = "koonktechnologies";
    $count = fb_fan_count($page);
    echo $count;
    ?>

7. 确定任意图片的主导颜色

    function dominant_color($image)
    {
    $i = imagecreatefromjpeg($image);
    for ($x=0;$x<imagesx($i);$x++) {
      for ($y=0;$y<imagesy($i);$y++) {
        $rgb = imagecolorat($i,$x,$y);
        $r  = ($rgb >> 16) & 0xFF;
        $g  = ($rgb >> & 0xFF;
        $b  = $rgb & 0xFF;
        $rTotal += $r;
        $gTotal += $g;
        $bTotal += $b;
        $total++;
      }
    }
    $rAverage = round($rTotal/$total);
    $gAverage = round($gTotal/$total);
    $bAverage = round($bTotal/$total);
    }

8. whois 查询
使用下面的函数可以获取任何域名用户的完整细节

    function whois_query($domain) {

      // fix the domain name:
      $domain = strtolower(trim($domain));
      $domain = preg_replace('/^http:\/\//i', '', $domain);
      $domain = preg_replace('/^www\./i', '', $domain);
      $domain = explode('/', $domain);
      $domain = trim($domain[0]);

      // split the TLD from domain name
      $_domain = explode('.', $domain);
      $lst = count($_domain)-1;
      $ext = $_domain[$lst];

      // You find resources and lists
      // like these on wikipedia:
      //
      // http://de.wikipedia.org/wiki/Whois
      //
      $servers = array(
        "biz" => "whois.neulevel.biz",
        "com" => "whois.internic.net",
        "us" => "whois.nic.us",
        "coop" => "whois.nic.coop",
        "info" => "whois.nic.info",
        "name" => "whois.nic.name",
        "net" => "whois.internic.net",
        "gov" => "whois.nic.gov",
        "edu" => "whois.internic.net",
        "mil" => "rs.internic.net",
        "int" => "whois.iana.org",
        "ac" => "whois.nic.ac",
        "ae" => "whois.uaenic.ae",
        "at" => "whois.ripe.net",
        "au" => "whois.aunic.net",
        "be" => "whois.dns.be",
        "bg" => "whois.ripe.net",
        "br" => "whois.registro.br",
        "bz" => "whois.belizenic.bz",
        "ca" => "whois.cira.ca",
        "cc" => "whois.nic.cc",
        "ch" => "whois.nic.ch",
        "cl" => "whois.nic.cl",
        "cn" => "whois.cnnic.net.cn",
        "cz" => "whois.nic.cz",
        "de" => "whois.nic.de",
        "fr" => "whois.nic.fr",
        "hu" => "whois.nic.hu",
        "ie" => "whois.domainregistry.ie",
        "il" => "whois.isoc.org.il",
        "in" => "whois.ncst.ernet.in",
        "ir" => "whois.nic.ir",
        "mc" => "whois.ripe.net",
        "to" => "whois.tonic.to",
        "tv" => "whois.tv",
        "ru" => "whois.ripn.net",
        "org" => "whois.pir.org",
        "aero" => "whois.information.aero",
        "nl" => "whois.domain-registry.nl"
      );

      if (!isset($servers[$ext])){
        die('Error: No matching nic server found!');
      }

      $nic_server = $servers[$ext];

      $output = '';

      // connect to whois server:
      if ($conn = fsockopen ($nic_server, 43)) {
        fputs($conn, $domain."\r\n");
        while(!feof($conn)) {
          $output .= fgets($conn,128);
        }
        fclose($conn);
      }
      else { die('Error: Could not connect to ' . $nic_server . '!'); }

      return $output;
    }

语法：

    <?php
    $domain = "http://www.blog.koonk.com";
    $result = whois_query($domain);
    print_r($result);
    ?>

9. 验证邮箱地址
有时候，当在网站填写表单，用户可能会输入错误的邮箱地址，这个函数可以验证邮箱地址是否有效。

    function is_validemail($email)
    {
    $check = 0;
    if(filter_var($email,FILTER_VALIDATE_EMAIL))
    {
    $check = 1;
    }
    return $check;
    }

语法：

    <?php
    $email = "blog@koonk.com";
    $check = is_validemail($email);
    echo $check;
    // If the output is 1, then email is valid.
    ?>

10. 获取用户的真实 IP

    function getRealIpAddr() 
    { 
      if (!emptyempty($_SERVER['HTTP_CLIENT_IP'])) 
      { 
        $ip=$_SERVER['HTTP_CLIENT_IP']; 
      } 
      elseif (!emptyempty($_SERVER['HTTP_X_FORWARDED_FOR'])) 
      //to check ip is pass from proxy 
      { 
        $ip=$_SERVER['HTTP_X_FORWARDED_FOR']; 
      } 
      else 
      { 
        $ip=$_SERVER['REMOTE_ADDR']; 
      } 
      return $ip; 
    }

语法：

    <?php
    $ip = getRealIpAddr();
    echo $ip;
    ?>

11. 转换 URL：从字符串变成超链接
如果你正在开发论坛，博客或者是一个常规的表单提交，很多时候都要用户访问一个网站。使用这个函数，URL 字符串就可以自动的转换为超链接。

    function makeClickableLinks($text)
    { 
     $text = eregi_replace('(((f|ht){1}tp://)[-a-zA-Z0-9@:%_+.~#?&//=]+)', 
     '<a href="\1">\1</a>', $text); 
     $text = eregi_replace('([[:space:]()[{}])(www.[-a-zA-Z0-9@:%_+.~#?&//=]+)', 
     '\1<a href="http://\2">\2</a>', $text); 
     $text = eregi_replace('([_.0-9a-z-]+@([0-9a-z][0-9a-z-]+.)+[a-z]{2,3})', 
     '<a href="mailto:\1">\1</a>', $text); 

    return $text; 
    }

语法：

    <?php
    $text = "This is my first post on http://blog.koonk.com";
    $text = makeClickableLinks($text);
    echo $text;
    ?>

12. 阻止多个 IP 访问你的网站
这个代码片段可以方便你禁止某些特定的 IP 地址访问你的网站

    if ( !file_exists('blocked_ips.txt') ) {
     $deny_ips = array(
     '127.0.0.1',
     '192.168.1.1',
     '83.76.27.9',
     '192.168.1.163'
     );
    } else {
     $deny_ips = file('blocked_ips.txt');
    }
    // read user ip adress:
    $ip = isset($_SERVER['REMOTE_ADDR']) ? trim($_SERVER['REMOTE_ADDR']) : '';

    // search current IP in $deny_ips array
    if ( (array_search($ip, $deny_ips))!== FALSE ) {
     // address is blocked:
     echo 'Your IP adress ('.$ip.') was blocked!';
     exit;
    }

13. 强制性文件下载
如果你需要下载特定的文件而不用另开新窗口，下面的代码片段可以帮助你。

    function force_download($file)
    {
      $dir   = "../log/exports/";
      if ((isset($file))&&(file_exists($dir.$file))) {
        header("Content-type: application/force-download");
        header('Content-Disposition: inline; filename="' . $dir.$file . '"');
        header("Content-Transfer-Encoding: Binary");
        header("Content-length: ".filesize($dir.$file));
        header('Content-Type: application/octet-stream');
        header('Content-Disposition: attachment; filename="' . $file . '"');
        readfile("$dir$file");
      } else {
        echo "No file selected";
      }
    }

语法：

    <php
    force_download("image.jpg");
    ?>

14. 创建 JSON 数据
使用下面的 PHP 片段可以创建 JSON 数据，可以方便你创建移动应用的 Web 服务

    $json_data = array ('id'=>1,'name'=>"Mohit");
    echo json_encode($json_data);

15. 压缩 zip 文件
使用下面的 PHP 片段可以即时压缩 zip 文件

    function create_zip($files = array(),$destination = '',$overwrite = false) { 
      //if the zip file already exists and overwrite is false, return false 
      if(file_exists($destination) && !$overwrite) { return false; } 
      //vars 
      $valid_files = array(); 
      //if files were passed in... 
      if(is_array($files)) { 
        //cycle through each file 
        foreach($files as $file) { 
          //make sure the file exists 
          if(file_exists($file)) { 
            $valid_files[] = $file; 
          } 
        } 
      } 
      //if we have good files... 
      if(count($valid_files)) { 
        //create the archive 
        $zip = new ZipArchive(); 
        if($zip->open($destination,$overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true) { 
          return false; 
        } 
        //add the files 
        foreach($valid_files as $file) { 
          $zip->addFile($file,$file); 
        } 
        //debug 
        //echo 'The zip archive contains ',$zip->numFiles,' files with a status of ',$zip->status; 

        //close the zip -- done! 
        $zip->close(); 

        //check to make sure the file exists 
        return file_exists($destination); 
      } 
      else 
      { 
        return false; 
      } 
    }

语法：

    <?php
    $files=array('file1.jpg', 'file2.jpg', 'file3.gif'); 
    create_zip($files, 'myzipfile.zip', true);
    ?>

16. 解压文件

    function unzip($location,$newLocation)
    {
        if(exec("unzip $location",$arr)){
          mkdir($newLocation);
          for($i = 1;$i< count($arr);$i++){
            $file = trim(preg_replace("~inflating: ~","",$arr[$i]));
            copy($location.'/'.$file,$newLocation.'/'.$file);
            unlink($location.'/'.$file);
          }
          return TRUE;
        }else{
          return FALSE;
        }
    }

语法：

    <?php
    unzip('test.zip','unziped/test'); //File would be unzipped in unziped/test folder
    ?>

17. 缩放图片

    function resize_image($filename, $tmpname, $xmax, $ymax) 
    { 
      $ext = explode(".", $filename); 
      $ext = $ext[count($ext)-1]; 

      if($ext == "jpg" || $ext == "jpeg") 
        $im = imagecreatefromjpeg($tmpname); 
      elseif($ext == "png") 
        $im = imagecreatefrompng($tmpname); 
      elseif($ext == "gif") 
        $im = imagecreatefromgif($tmpname); 

      $x = imagesx($im); 
      $y = imagesy($im); 

      if($x <= $xmax && $y <= $ymax) 
        return $im; 

      if($x >= $y) { 
        $newx = $xmax; 
        $newy = $newx * $y / $x; 
      } 
      else { 
        $newy = $ymax; 
        $newx = $x / $y * $newy; 
      } 

      $im2 = imagecreatetruecolor($newx, $newy); 
      imagecopyresized($im2, $im, 0, 0, 0, 0, floor($newx), floor($newy), $x, $y); 
      return $im2; 
    }

18. 使用 mail() 发送邮件
之前我们提供了如何使用 Mandrill 发送邮件的 PHP 代码片段，但是如果你不想使用第三方服务，那么可以使用下面的 PHP 代码片段。

    function send_mail($to,$subject,$body)
    {
    $headers = "From: KOONK\r\n";
    $headers .= "Reply-To: blog@koonk.com\r\n";
    $headers .= "Return-Path: blog@koonk.com\r\n";
    $headers .= "X-Mailer: PHP5\n";
    $headers .= 'MIME-Version: 1.0' . "\n";
    $headers .= 'Content-type: text/html; charset=iso-8859-1' . "\r\n";
    mail($to,$subject,$body,$headers);
    }

语法：

    <?php
    $to = "admin@koonk.com";
    $subject = "This is a test mail";
    $body = "Hello World!";
    send_mail($to,$subject,$body);
    ?>

19. 把秒转换成天数，小时数和分钟

    function secsToStr($secs) {
      if($secs>=86400){$days=floor($secs/86400);$secs=$secs%86400;$r=$days.' day';if($days<>1){$r.='s';}if($secs>0){$r.=', ';}}
      if($secs>=3600){$hours=floor($secs/3600);$secs=$secs%3600;$r.=$hours.' hour';if($hours<>1){$r.='s';}if($secs>0){$r.=', ';}}
      if($secs>=60){$minutes=floor($secs/60);$secs=$secs%60;$r.=$minutes.' minute';if($minutes<>1){$r.='s';}if($secs>0){$r.=', ';}}
      $r.=$secs.' second';if($secs<>1){$r.='s';}
      return $r;
    }

语法：

    <?php
    $seconds = "56789";
    $output = secsToStr($seconds);
    echo $output;
    ?>

20. 数据库连接
连接 MySQL 数据库

    <?php
    $DBNAME = 'koonk';
    $HOST = 'localhost';
    $DBUSER = 'root';
    $DBPASS = 'koonk';
    $CONNECT = mysql_connect($HOST,$DBUSER,$DBPASS);
    if(!$CONNECT)
    {
      echo 'MySQL Error: '.mysql_error();
    }
    $SELECT = mysql_select_db($DBNAME);
    if(!$SELECT)
    {
      echo 'MySQL Error: '.mysql_error();
    }
    ?>

21. 目录清单
使用下面的 PHP 代码片段可以在一个目录中列出所有文件和文件夹

    function list_files($dir)
    {
      if(is_dir($dir))
      {
        if($handle = opendir($dir))
        {
          while(($file = readdir($handle)) !== false)
          {
            if($file != "." && $file != ".." && $file != "Thumbs.db"/*pesky windows, images..*/)
            {
              echo '<a target="_blank" href="'.$dir.$file.'">'.$file.'</a>'."\n";
            }
          }
          closedir($handle);
        }
      }
    }

语法：

    <?php
      list_files("images/"); //This will list all files of images folder
    ?>

22. 检测用户语言
使用下面的 PHP 代码片段可以检测用户浏览器所使用的语言

    function get_client_language($availableLanguages, $default='en'){
      if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
        $langs=explode(',',$_SERVER['HTTP_ACCEPT_LANGUAGE']);
        foreach ($langs as $value){
          $choice=substr($value,0,2);
          if(in_array($choice, $availableLanguages)){
            return $choice;
          }
        }
      }
      return $default;
    }

23. 查看 CSV 文件

    function readCSV($csvFile){
      $file_handle = fopen($csvFile, 'r');
      while (!feof($file_handle) ) {
        $line_of_text[] = fgetcsv($file_handle, 1024);
      }
      fclose($file_handle);
      return $line_of_text;
    }

语法：

    <?php
    $csvFile = "test.csv";
    $csv = readCSV($csvFile);
    $a = csv[0][0]; // This will get value of Column 1 & Row 1
    ?>

以上就是本文的全部内容，希望对大家的学习有所帮助。