Summary of some commonly used functions in PHP (summary)

This article introduces to you a summary (summary) of some commonly used functions in PHP. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.

1. Get whether the website is http or https?

$http_type = ((isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') || (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https')) ? 'https://' : 'http://';

2. Delete the empty data in the array

function where_data($data) { foreach ($data as $k => $v) { if (empty($v) && $v !='0') { unset($data[$k]); } } return $data; }

3. Intercept part of the rich text

/** * 将富文本中文字截取其中的一部分 * @param $content * @return string */ function html_substr_content($content,$length=100) { $content = htmlspecialchars_decode($content); //把一些预定义的 HTML 实体转换为字符 $content = str_replace(" ", "", $content); //将空格替换成空 $content = strip_tags($content); //函数剥去字符串中的 HTML、XML 以及 PHP 的标签,获取纯文本内容 $con = mb_substr($content, 0, $length, "utf-8"); //返回字符串中的前100字符串长度的字符 return $con; }

1. Blacklist filtering

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

2. Random color generator

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();

3. Download files from the Internet

set_time_limit(0); // Supports all file types // URL Here: $url = '//m.sbmmt.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);

4. Forced file download

$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; }

5. Screen capture

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

6. Check Is the website down?

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";

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