10个超级有用和最爱收藏的PHP代码样例

作为一个正常的程序员，会好几种语言是十分正常的，相信大部分程序员也都会编写几句PHP程序，如果是WEB程序员，PHP一定是必备的，即使你没用它开发过大型软件项目，也一定多少了解它的语法。

尽管PHP经常被人诟病，被人贬低，被人当玩笑开，事实证明，PHP是全世界网站开发中使用率最高的编程语言。PHP最大的缺点是太简单，语法不严谨，框架体系很弱，但这也是它最大的优点，一个有点编程背景的普通人，只需要学习PHP半天时间，就可以上手开始开发web应用了。

网上有人总结几种编程语言的特点，我觉得也挺有道理的：

PHP 就是： Quick and Dirty

Java 就是： Beauty and Slowly

Ruby 就是： Quick and Beauty

python 就是： Quick and Simple

在PHP的流行普及中，网上总结出了很多实用的PHP代码片段，这些代码片段在当你遇到类似的问题时，粘贴过去就可以使用，非常的高效，非常的省时省力。将这些程序员前辈总结出的优秀代码放到自己的知识库中，是一个善于学习的程序员的好习惯。

一、黑名单过滤

ab:3

dog:3

cat:2

monkey:2

二、随机颜色生成器

function randomColor() {

$str = ‘#’;

for($i = 0 ; $i < 6 ; $i++) {

$randNum = rand(0 , 15);

switch ($randNum) {

case 10: $randNum = ‘A’; break ;

case 11: $randNum = ‘B’; break;

case 12: $randNum = ‘C’; break;

case 13: $randNum = ‘D’; break;

case 14: $randNum = ‘E’; break;

case 15: $randNum = ‘F’; break;

}

$str .= $randNum;

}

return $str;

}

$color = randomColor();

三、从网络下载文件

set_time_limit(0);

// Supports all file types

// URL Here:

$url = ‘

$ pi = pathinfo($url);

$ext = $pi[‘extension’];

$name = $pi[‘filename’];

// create a new cURL resource

$ch = curl_init();

// set URL and other appropriate options

curl_setopt($ch, CURLOPT_URL, $url);

curl_setopt($ch, CURLOPT_ header , false);

curl_setopt($ch, CURLOPT_BINARYTRANSFER, true);

curl_setopt($ch, CURLOPT_AUTOREFERER, true);

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

// grab URL and pass it to the browser

$opt = curl_exec($ch);

// close cURL resource, and free up system resources

curl_close($ch);

$saveFile = $name.’.’.$ext;

if(preg_match(“/[^0-9a-z._-]/i”, $saveFile))

$saveFile = md5(microtime(true)).’.’.$ext;

$handle = fopen($saveFile, ‘wb’);

fwrite($handle, $opt);

fclose($handle);

四、Alexa/Google Page Rank

function page_rank($page, $type = ‘alexa’){

switch($type){

case ‘alexa’:

$url = ‘

$handle = fopen($url.$page, ‘r’);

break;

case ‘google’:

$url = ‘

$handle = fopen($url.’ ‘r’);

break;

}

$content = stream_get_contents($handle);

fclose($handle);

$content = preg_replace(“~(n|t|ss+)~”,”, $content);

switch($type){

case ‘alexa’:

if(preg_match(‘~

(.+?)

~im’,$content,$matches)){

return $matches[2];

}else{

return FALSE;

}

break;

case ‘google’:

$rank = explode(‘:’,$content);

if($rank[2] != ”)

return $rank[2];

else

return FALSE;

break;

default:

return FALSE;

break;

}

}

// Alexa Page Rank:

echo ‘Alexa Rank: ‘.page_rank(‘techug.com’);

echo ‘

‘;

// Google Page Rank

echo ‘Google Rank: ‘.page_rank(‘techug.com’, ‘google’);

五、强制下载文件

$filename = $_GET[‘file’]; //Get the fileid from the URL

// Query the file ID

$query = sprintf(“SELECT * FROM tableName WHERE id = ‘%s'”,my sql _real_escape_string($filename));

$sql = mysql_query($query);

if(mysql_num_rows($sql) > 0){

$row = mysql_fetch_array($sql);

// Set some headers

header(“Pragma: public”);

header(“Expires: 0”);

header(“Cache-Control: must-revalidate, post-check=0, pre-check=0”);

header(“Content-Type: application/force-download”);

header(“Content-Type: application/octet-stream”);

header(“Content-Type: application/download”);

header(“Content-Disposition: attachment; filename=”.basename($row[‘FileName’]).”;”);

header(“Content-Transfer-Encoding: binary”);

header(“Content-Length: “.filesize($row[‘FileName’]));

@readfile($row[‘FileName’]);

exit(0);

}else{

header(“Location: /”);

exit;

}

六、通过Email显示用户的Gravatar头像

$gravatar_link = ‘ . md5($comment_author_email) . ‘?s=32’;

echo ‘’;

七、通过cURL获取RSS订阅数

$ch = curl_init();

curl_setopt($ch,CURLOPT_URL,’

curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);

curl_setopt($ch,CURLOPT_CONNECTTIMEOUT,2);

$content = curl_exec($ch);

$subscribers = get_match(‘/circulation=”(.*)”/isU’,$content);

curl_close($ch);

八、时间差异计算函数

function ago($time)

{

$periods = array(“second”, “minute”, “hour”, “day”, “week”, “month”, “year”, “decade”);

$lengths = array(“60″,”60″,”24″,”7″,”4.35″,”12″,”10”);

$now = time();

$difference = $now – $time;

$tense = “ago”;

for($j = 0; $difference >= $lengths[$j] && $j < count($lengths)-1; $j++) {

$difference /= $lengths[$j];

}

$difference = round($difference);

if($difference != 1) {

$periods[$j].= “s”;

}

return “$difference $periods[$j] ‘ago’ “;

}

九、裁剪图片

$filename= “test.jpg”;

list($w, $h, $type, $attr) = getimagesize($filename);

$src_im = imagecreatefromjpeg($filename);

$src_x = ‘0’; // begin x

$src_y = ‘0’; // begin y

$src_w = ‘100’; // width

$src_h = ‘100’; // height

$dst_x = ‘0’; // destination x

$dst_y = ‘0’; // destination y

$dst_im = imagecreatetruecolor($src_w, $src_h);

$white = imagecolorallocate($dst_im, 255, 255, 255);

imagefill($dst_im, 0, 0, $white);

imagecopy($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h);

header(“Content-type: image/png”);

imagepng($dst_im);

imagedestroy($dst_im);

十、检查网站是否宕机

function Visit($url){

$agent = “Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)”;$ch=curl_init();

curl_setopt ($ch, CURLOPT_URL,$url );

curl_setopt($ch, CURLOPT_USERAGENT, $agent);

curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);

curl_setopt ($ch,CURLOPT_VERBOSE,false);

curl_setopt($ch, CURLOPT_TIMEOUT, 5);

curl_setopt($ch,CURLOPT_SSL_VERIFYPEER, FALSE);

curl_setopt($ch,CURLOPT_SSLVERSION,3);

curl_setopt($ch,CURLOPT_SSL_VERIFYHOST, FALSE);

$page=curl_exec($ch);

//echo curl_error($ch);

$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);

curl_close($ch);

if($httpcode>=200 && $httpcode<300) return true;

else return false;

}

if (Visit(“”))

echo “Website OK”.”n”;

else

echo “Website DOWN”;