PHP中6个好用的代码片段

小编给大家分享一下PHP中6个好用的代码片段，相信大部分人都还不怎么了解，因此分享这篇文章给大家参考一下，希望大家阅读完这篇文章后大有收获，下面让我们一起去了解一下吧！

一、黑名单过滤

function is_spam($text, $file, $split = ':', $regex = false){   $handle = fopen($file, 'rb');   $contents = fread($handle, filesize($file));   fclose($handle);   $lines = explode("n", $contents); $arr = array(); foreach($lines as $line){ list($word, $count) = explode($split, $line); if($regex) $arr[$word] = $count; else $arr[preg_quote($word)] = $count; } preg_match_all("~".implode('|', array_keys($arr))."~", $text, $matches); $temp = array(); foreach($matches[0] as $match){ if(!in_array($match, $temp)){ $temp[$match] = $temp[$match] + 1; if($temp[$match] >= $arr[$word]) return true; } } return false; }  $file = 'spam.txt'; $str = 'This string has cat, dog word'; if(is_spam($str, $file)) echo 'this is spam'; else echo 'this is not spam';  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、从网上下载文件

set_time_limit(0); // Supports all file types // URL Here: $url = 'http://somsite.com/some_video.flv'; $pi = pathinfo($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、强制下载文件

$filename = $_GET['file']; //Get the fileid from the URL // Query the file ID $query = sprintf("SELECT * FROM tableName WHERE id = '%s'",mysql_real_escape_string($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; }

五、截取图片

$filename= "test.jpg"; list($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);

六、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("http://www.google.com")) echo "Website OK"."n"; else echo "Website DOWN";

以上是"PHP中6个好用的代码片段"这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注行业资讯频道！