7個(gè)超級(jí)實(shí)用的PHP代碼片段分享
1、超級(jí)簡(jiǎn)單的頁(yè)面緩存
如果你的工程項(xiàng)目不是基于 CMS 系統(tǒng)或框架，打造一個(gè)簡(jiǎn)單的緩存系統(tǒng)將會(huì)非常實(shí)在。下面的代碼很簡(jiǎn)單，但是對(duì)小網(wǎng)站而言能切切實(shí)實(shí)解決問(wèn)題。
- <?php
- // define the path and name of cached file
- $cachefile = 'cached-files/'.date('M-d-Y').'.php';
- // define how long we want to keep the file in seconds. I set mine to 5 hours.
- $cachetime = 18000;
- // Check if the cached file is still fresh. If it is, serve it up and exit.
- if (file_exists($cachefile) && time() - $cachetime < filemtime($cachefile)) {
- include($cachefile);
- exit;
- }
- // if there is either no file OR the file to too old, render the page and capture the HTML.
- ob_start();
- ?>
- <html>
- output all your html here.
- </html>
- <?php
- // We're done! Save the cached content to a file
- $fp = fopen($cachefile, 'w');
- fwrite($fp, ob_get_contents());
- fclose($fp);
- // finally send browser output
- ob_end_flush();
- ?>
點(diǎn)擊這里查看詳細(xì)情況：http://wesbos.com/simple-php-page-caching-technique/
2、在 PHP 中計(jì)算距離
這是一個(gè)非常有用的距離計(jì)算函數(shù)，利用緯度和經(jīng)度計(jì)算從 A 地點(diǎn)到 B 地點(diǎn)的距離。該函數(shù)可以返回英里，公里，海里三種單位類(lèi)型的距離。
- function distance($lat1, $lon1, $lat2, $lon2, $unit) {
- $theta = $lon1 - $lon2;
- $dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) + cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta));
- $dist = acos($dist);
- $dist = rad2deg($dist);
- $miles = $dist * 60 * 1.1515;
- $unit = strtoupper($unit);
- if ($unit == "K") {
- return ($miles * 1.609344);
- } else if ($unit == "N") {
- return ($miles * 0.8684);
- } else {
- return $miles;
- }
- }
使用方法：
- echo distance(32.9697, -96.80322, 29.46786, -98.53506, "k")." kilometers";
點(diǎn)擊這里查看詳細(xì)情況：http://www.phpsnippets.info/calculate-distances-in-php
3、將秒數(shù)轉(zhuǎn)換為時(shí)間(年、月、日、小時(shí)…)
這個(gè)有用的函數(shù)能將秒數(shù)表示的事件轉(zhuǎn)換為年、月、日、小時(shí)等時(shí)間格式。
- function Sec2Time($time){
- if(is_numeric($time)){
- $value = array(
- "years" => 0, "days" => 0, "hours" => 0,
- "minutes" => 0, "seconds" => 0,
- );
- if($time >= 31556926){
- $value["years"] = floor($time/31556926);
- $time = ($time%31556926);
- }
- if($time >= 86400){
- $value["days"] = floor($time/86400);
- $time = ($time%86400);
- }
- if($time >= 3600){
- $value["hours"] = floor($time/3600);
- $time = ($time%3600);
- }
- if($time >= 60){
- $value["minutes"] = floor($time/60);
- $time = ($time%60);
- }
- $value["seconds"] = floor($time);
- return (array) $value;
- }else{
- return (bool) FALSE;
- }
- }
點(diǎn)擊這里查看詳細(xì)情況：http://ckorp.net/sec2time.php
#p#
4、強(qiáng)制下載文件
一些諸如 mp3 類(lèi)型的文件，通常會(huì)在客戶(hù)端瀏覽器中直接被播放或使用。如果你希望它們強(qiáng)制被下載，也沒(méi)問(wèn)題?？梢允褂靡韵麓a：
- function downloadFile($file){
- $file_name = $file;
- $mime = 'application/force-download';
- header('Pragma: public'); // required
- header('Expires: 0'); // no cache
- header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
- header('Cache-Control: private',false);
- header('Content-Type: '.$mime);
- header('Content-Disposition: attachment; filename="'.basename($file_name).'"');
- header('Content-Transfer-Encoding: binary');
- header('Connection: close');
- readfile($file_name); // push it out
- exit();
- }
點(diǎn)擊這里查看詳細(xì)情況：http://www.tecnocrazia.com/
5、使用 Google API 獲取當(dāng)前天氣信息
想知道今天的天氣?這段代碼會(huì)告訴你，只需 3 行代碼。你只需要把其中的 ADDRESS 換成你期望的城市。
- $xml = simplexml_load_file('http://www.google.com/ig/api?weather=ADDRESS');
- $information = $xml->xpath("/xml_api_reply/weather/current_conditions/condition");
- echo $information[0]->attributes();
點(diǎn)擊這里查看詳細(xì)情況：http://ortanotes.tumblr.com/post/200469319/current-weather-in-3-lines-of-php
6、獲得某個(gè)地址的經(jīng)緯度
隨著 Google Maps API 的普及，開(kāi)發(fā)人員常常需要獲得某一特定地點(diǎn)的經(jīng)度和緯度。這個(gè)非常有用的函數(shù)以某一地址作為參數(shù)，返回一個(gè)數(shù)組，包含經(jīng)度和緯度數(shù)據(jù)。
- function getLatLong($address){
- if (!is_string($address))die("All Addresses must be passed as a string");
- $_url = sprintf('http://maps.google.com/maps?output=js&q=%s',rawurlencode($address));
- $_result = false;
- if($_result = file_get_contents($_url)) {
- if(strpos($_result,'errortips') > 1 || strpos($_result,'Did you mean:') !== false) return false;
- preg_match('!center:\s*{lat:\s*(-?\d+\.\d+),lng:\s*(-?\d+\.\d+)}!U', $_result, $_match);
- $_coords['lat'] = $_match[1];
- $_coords['long'] = $_match[2];
- }
- return $_coords;
- }
點(diǎn)擊這里查看詳細(xì)情況：http://snipplr.com/view.php?codeview&id=47806
7、使用 PHP 和 Google 獲取域名的 favicon 圖標(biāo)
有些網(wǎng)站或 Web 應(yīng)用程序需要使用來(lái)自其他網(wǎng)站的 favicon 圖標(biāo)。利用 Google 和 PHP 很容易就能搞定，不過(guò)前提是 Google 不會(huì)連接被重置哦!
- function get_favicon($url){
- $url = str_replace("http://",'',$url);
- return "http://www.google.com/s2/favicons?domain=".$url;
- }
點(diǎn)擊這里查看詳細(xì)情況：http://snipplr.com/view.php?codeview&id=45928
原文：http://www.mangguo.org/7-super-useful-php-snippets/
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