56个 PHP 开发常用代码片段（中）
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 $default;
}- 查看 CSV 文件
function readCSV($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);
$a = csv[0][0]; // This will get value of Column 1 & Row 1
?>- 从 PHP 数据创建 CSV 文件
function generateCsv($data, $delimiter = ',', $enclosure = '"') {
$handle = fopen('php://temp', 'r+');
foreach ($data as $line) {
fputcsv($handle, $line, $delimiter, $enclosure);
}
rewind($handle);
while (!feof($handle)) {
$contents .= fread($handle, 8192);
}
fclose($handle);
return $contents;
}语法：
<?php
$data[0] = "apple";
$data[1] = "oranges";
generateCsv($data, $delimiter = ',', $enclosure = '"');
?>25. 解析 XML 数据
$xml_string="<?xml version='1.0'?>
<moleculedb>
<molecule name='Benzine'>
<symbol>ben</symbol>
<code>A</code>
</molecule>
<molecule name='Water'>
<symbol>h2o</symbol>
<code>K</code>
</molecule>
</moleculedb>";
//load the xml string using simplexml function
$xml = simplexml_load_string($xml_string);
//loop through the each node of molecule
foreach ($xml->molecule as $record)
{
//attribute are accessted by
echo $record['name'], ' ';
//node are accessted by -> operator
echo $record->symbol, ' ';
echo $record->code, '';
}26. 解析 JSON 数据
$json_string='{"id":1,"name":"rolf","country":"russia","office":["google","oracle"]} ';
$obj=json_decode($json_string);
//print the parsed data
echo $obj->name; //displays rolf
echo $obj->office[0]; //displays google27. 获取当前页面 URL
这个 PHP 片段可以帮助你让用户登录后直接跳转到之前浏览的页面
function current_url()
{
$url = "http://" . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
$validURL = str_replace("&", "&", $url);
return validURL;
}语法：
<?php
echo "Currently you are on: ".current_url();
?>28. 从任意的 Twitter 账号获取最新的 Tweet
function my_twitter($username)
{
$no_of_tweets = 1;
$feed = "http://search.twitter.com/search.atom?q=from:" . $username . "&rpp=" . $no_of_tweets;
$xml = simplexml_load_file($feed);
foreach($xml->children() as $child) {
foreach ($child as $value) {
if($value->getName() == "link") $link = $value['href'];
if($value->getName() == "content") {
$content = $value . "";
echo '<p class="twit">'.$content.' <a class="twt" href="'.$link.'" title=""> </a></p>';
}
}
}
}语法：
<?php
$handle = "koonktech";
my_twitter($handle);
?>29. 转发数量
使用这个 PHP 片段可以检测你的页面 URL 有多少转发数量
function tweetCount($url) {
$content = file_get_contents("http://api.tweetmeme.com/url_info?url=".$url);
$element = new SimpleXmlElement($content);
$retweets = $element->story->url_count;
if($retweets){
return $retweets;
} else {
return 0;
}
}语法：
<?php
$url = "http://blog.koonk.com";
$count = tweetCount($url);
return $count;
?>30. 计算两个日期的差
<?php
$date1 = date( 'Y-m-d' );
$date2 = "2015-12-04";
$diff = abs(strtotime($date2) - strtotime($date1));
$years = floor($diff / (365*60*60*24));
$months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
$days = floor(($diff - $years * 365*60*60*24 - $months*30*60*60*24)/ (60*60*24));
printf("%d years, %d months, %d days\n", $years, $months, $days);
-------------------------------------------------------- OR
$date1 = new DateTime("2007-03-24");
$date2 = new DateTime("2009-06-26");
$interval = $date1->diff($date2);
echo "difference " . $interval->y . " years, " . $interval->m." months, ".$interval->d." days ";
// shows the total amount of days (not divided into years, months and days like above)
echo "difference " . $interval->days . " days ";
-------------------------------------------------------- OR
/**
* Calculate differences between two dates with precise semantics. Based on PHPs DateTime::diff()
* implementation by Derick Rethans. Ported to PHP by Emil H, 2011-05-02. No rights reserved.
*
* See here for original code:
* http://svn.php.net/viewvc/php/php-src/trunk/ext/date/lib/tm2unixtime.c?revision=302890&view=markup
* http://svn.php.net/viewvc/php/php-src/trunk/ext/date/lib/interval.c?revision=298973&view=markup
*/
function _date_range_limit($start, $end, $adj, $a, $b, $result)
{
if ($result[$a] < $start) {
$result[$b] -= intval(($start - $result[$a] - 1) / $adj)