比较有用的php代码片断

比较有用的php代码片段

一 从网页中提取关键词

$meta = get_meta_tags(<span style="color: #800000;">'</span><span style="color: #800000;">http://www.emoticode.net/</span><span style="color: #800000;">'</span><span style="color: #000000;">);$keywords </span>= $meta[<span style="color: #800000;">'</span><span style="color: #800000;">keywords</span><span style="color: #800000;">'</span><span style="color: #000000;">];</span><span style="color: #008000;">//</span><span style="color: #008000;"> Split keywords</span>$keywords = explode(<span style="color: #800000;">'</span><span style="color: #800000;">,</span><span style="color: #800000;">'</span><span style="color: #000000;">, $keywords );</span><span style="color: #008000;">//</span><span style="color: #008000;"> Trim them</span>$keywords = array_map( <span style="color: #800000;">'</span><span style="color: #800000;">trim</span><span style="color: #800000;">'</span><span style="color: #000000;">, $keywords );</span><span style="color: #008000;">//</span><span style="color: #008000;"> Remove empty values</span>$keywords =<span style="color: #000000;"> array_filter( $keywords );print_r( $keywords );</span>

二 查找页面上的所有链接

<span style="color: #000000;">使用DOM，你可以在任意页面上抓取链接，示例如下。</span>

1. $html = file_get_contents('http://www.example.com');
2.  
3. $dom = new DOMDocument();
4. @$dom->loadHTML($html);
5.  
6. // grab all the on the page
7. $xpath = new DOMXPath($dom);
8. $hrefs = $xpath->evaluate("/html/body//a");
9.  
10. for ($i = 0; $i $hrefs->length; $i++) {
11. $href = $hrefs->item($i);
12. $url = $href->getAttribute('href');
13. echo $url.'
    ';
14. }

    三 创建数据URI

    数据URI可以帮助将图像嵌入到HTML/CSS/<span style="color: #000000;">JS中，从而节省HTTP请求。下面的函数可以利用$file创建数据URI。 function data_uri($file, $mime) {    $contents</span>=<span style="color: #000000;">file_get_contents($file);    $base64</span>=<span style="color: #000000;">base64_encode($contents);    echo </span><span style="color: #800000;">"</span><span style="color: #800000;">data:$mime;base64,$base64</span><span style="color: #800000;">"</span><span style="color: #000000;">;}</span>

    四 下载和保存远程图片到你的服务器

    <span style="color: #000000;">当你在搭建网站时，很可能会从远程服务器上下载图片保存到你自己的服务器上，下面的代码就可以帮助你实现这个功能。$image </span>= file_get_contents(<span style="color: #800000;">'</span><span style="color: #800000;">http://www.php100.com/image.jpg</span><span style="color: #800000;">'</span><span style="color: #000000;">);file_put_contents(</span><span style="color: #800000;">'</span><span style="color: #800000;">/images/image.jpg</span><span style="color: #800000;">'</span>, $image);   <span style="color: #008000;">//</span><span style="color: #008000;">Where to save the image</span>

    五 移除Microsoft Word HTML标签

    <span style="color: #000000;"> 当你使用Microsoft Word时，会创建很多标签tag，比如font、span、style、class等，这些标签在Word中十分有用，但当你从Word中把文本粘贴到网页上，就会出现很多没用的标签。下面实用的函数可以帮助你清除所有的Word HTML标签。function cleanHTML($html) {</span><span style="color: #808080;">///</span> <span style="color: #808080;">///</span><span style="color: #008000;"> Removes all FONT and SPAN tags, and all Class and Style attributes.</span><span style="color: #808080;">///</span><span style="color: #008000;"> Designed to get rid of non-standard Microsoft Word HTML tags.</span><span style="color: #808080;">///</span> <span style="color: #008000;">//</span><span style="color: #008000;"> start by completely removing all unwanted tags</span><span style="color: #000000;">$html </span>= ereg_replace(<span style="color: #800000;">"</span><span style="color: #800000;">]*></span><span style="color: #800000;">"</span>,<span style="color: #800000;">""</span><span style="color: #000000;">,$html);</span><span style="color: #008000;">//</span><span style="color: #008000;"> then run another pass over the html (twice), removing unwanted attributes</span><span style="color: #000000;">$html </span>= ereg_replace(<span style="color: #800000;">"</span><span style="color: #800000;">]*)(class|lang|style|size|face)=(</span><span style="color: #800000;">"</span>[^<span style="color: #800000;">"</span><span style="color: #800000;">]*</span><span style="color: #800000;">"</span>|<span style="color: #800000;">'</span><span style="color: #800000;">[^</span><span style="color: #800000;">'</span>]*<span style="color: #800000;">'</span><span style="color: #800000;">|[^>]+)([^>]*)>","",$html);</span>$html = ereg_replace(<span style="color: #800000;">"</span><span style="color: #800000;">]*)(class|lang|style|size|face)=(</span><span style="color: #800000;">"</span>[^<span style="color: #800000;">"</span><span style="color: #800000;">]*</span><span style="color: #800000;">"</span>|<span style="color: #800000;">'</span><span style="color: #800000;">[^</span><span style="color: #800000;">'</span>]*<span style="color: #800000;">'</span><span style="color: #800000;">|[^>]+)([^>]*)>","",$html);</span><span style="color: #0000ff;">return</span><span style="color: #000000;"> $html}</span>

    六 检测浏览器语言

    <span style="color: #000000;">如果你的网站是多种语言的，下面的代码可以帮助你检测浏览器语言，它会返回客户端浏览器的默认语言。function get_client_language($availableLanguages, $</span><span style="color: #0000ff;">default</span>=<span style="color: #800000;">'</span><span style="color: #800000;">en</span><span style="color: #800000;">'</span><span style="color: #000000;">){    </span><span style="color: #0000ff;">if</span> (isset($_SERVER[<span style="color: #800000;">'</span><span style="color: #800000;">HTTP_ACCEPT_LANGUAGE</span><span style="color: #800000;">'</span><span style="color: #000000;">])) {          $langs</span>=explode(<span style="color: #800000;">'</span><span style="color: #800000;">,</span><span style="color: #800000;">'</span>,$_SERVER[<span style="color: #800000;">'</span><span style="color: #800000;">HTTP_ACCEPT_LANGUAGE</span><span style="color: #800000;">'</span><span style="color: #000000;">]);          </span><span style="color: #0000ff;">foreach</span> ($langs <span style="color: #0000ff;">as</span><span style="color: #000000;"> $value){              $choice</span>=substr($value,<span style="color: #800080;">0</span>,<span style="color: #800080;">2</span><span style="color: #000000;">);              </span><span style="color: #0000ff;">if</span><span style="color: #000000;">(in_array($choice, $availableLanguages)){                    </span><span style="color: #0000ff;">return</span><span style="color: #000000;"> $choice;              }          }      }       </span><span style="color: #0000ff;">return</span> $<span style="color: #0000ff;">default</span><span style="color: #000000;">;}</span>

    七 保存请求信息到本地

    file_put_contents(<span style="color: #800000;">'</span><span style="color: #800000;">/tmp/all.log</span><span style="color: #800000;">'</span>,<span style="color: #800000;">'</span><span style="color: #800000;">mapping</span><span style="color: #800000;">'</span>.date(<span style="color: #800000;">"</span><span style="color: #800000;">m-d H:i:s</span><span style="color: #800000;">"</span>).<span style="color: #800000;">"</span><span style="color: #800000;">\n</span><span style="color: #800000;">"</span>,FILE_APPEND);

    八 excel相互转换日期

    <span style="color: #0000ff;">//如果去获取某个excel日期（格式为：2016-03-12），那么获取到的是数字，需要经过转换才能恢复<br>public</span> function excelTime($date, $time = <span style="color: #0000ff;">false</span><span style="color: #000000;">) {            </span><span style="color: #0000ff;">if</span>(function_exists(<span style="color: #800000;">'</span><span style="color: #800000;">GregorianToJD</span><span style="color: #800000;">'</span><span style="color: #000000;">)){                </span><span style="color: #0000ff;">if</span><span style="color: #000000;"> (is_numeric( $date )) {                $jd </span>= GregorianToJD( <span style="color: #800080;">1</span>, <span style="color: #800080;">1</span>, <span style="color: #800080;">1970</span><span style="color: #000000;"> );                $gregorian </span>= JDToGregorian( $jd + intval ( $date ) - <span style="color: #800080;">25569</span><span style="color: #000000;"> );                $date </span>= explode( <span style="color: #800000;">'</span><span style="color: #800000;">/</span><span style="color: #800000;">'</span><span style="color: #000000;">, $gregorian );                $date_str </span>= str_pad( $date [<span style="color: #800080;">2</span>], <span style="color: #800080;">4</span>, <span style="color: #800000;">'</span><span style="color: #800000;">0</span><span style="color: #800000;">'</span><span style="color: #000000;">, STR_PAD_LEFT )                .</span><span style="color: #800000;">"</span><span style="color: #800000;">-</span><span style="color: #800000;">"</span>. str_pad( $date [<span style="color: #800080;">0</span>], <span style="color: #800080;">2</span>, <span style="color: #800000;">'</span><span style="color: #800000;">0</span><span style="color: #800000;">'</span><span style="color: #000000;">, STR_PAD_LEFT )                .</span><span style="color: #800000;">"</span><span style="color: #800000;">-</span><span style="color: #800000;">"</span>. str_pad( $date [<span style="color: #800080;">1</span>], <span style="color: #800080;">2</span>, <span style="color: #800000;">'</span><span style="color: #800000;">0</span><span style="color: #800000;">'</span><span style="color: #000000;">, STR_PAD_LEFT )                . ($time </span>? <span style="color: #800000;">"</span><span style="color: #800000;"> 00:00:00</span><span style="color: #800000;">"</span> : <span style="color: #800000;">''</span><span style="color: #000000;">);                </span><span style="color: #0000ff;">return</span><span style="color: #000000;"> $date_str;                }            }</span><span style="color: #0000ff;">else</span><span style="color: #000000;">{               </span><span style="color: #008000;">//</span><span style="color: #008000;"> $date=$date>25568? $date+1:25569;</span>                <span style="color: #008000;">/*</span><span style="color: #008000;">There was a bug if Converting date before 1-1-1970 (tstamp 0)</span><span style="color: #008000;">*/</span><span style="color: #000000;">                $ofs</span>=(<span style="color: #800080;">70</span> * <span style="color: #800080;">365</span> + <span style="color: #800080;">17</span>+<span style="color: #800080;">2</span>) * <span style="color: #800080;">86400</span><span style="color: #000000;">;                $date </span>= date(<span style="color: #800000;">"</span><span style="color: #800000;">Y-m-d</span><span style="color: #800000;">"</span>,($date * <span style="color: #800080;">86400</span>) - $ofs).($time ? <span style="color: #800000;">"</span><span style="color: #800000;"> 00:00:00</span><span style="color: #800000;">"</span> : <span style="color: #800000;">''</span><span style="color: #000000;">);                </span><span style="color: #0000ff;">return</span><span style="color: #000000;"> $date;            }    }</span>

    9 json与数据相互转换

    <span style="color: #800080;">1</span><span style="color: #000000;"> json转换成数组$json </span>= <span style="color: #800000;">'</span><span style="color: #800000;">[{"id":"22","name":"33","descn":"44"}]</span><span style="color: #800000;">'</span>; <span style="color: #008000;">//</span><span style="color: #008000;">json格式的数组转换成 php的数组</span>$arr =<span style="color: #000000;"> (Array)json_decode($json);echo $arr[</span><span style="color: #800080;">0</span>]->id; <span style="color: #008000;">//</span><span style="color: #008000;">用对象的方式访问（这种是没有转换成数组，而是转换成对象的情况</span>

    <span style="color: #800080;">2</span><span style="color: #000000;"> 数组转换成json$json_arr </span>= array(<span style="color: #800000;">'</span><span style="color: #800000;">WebName</span><span style="color: #800000;">'</span>=><span style="color: #800000;">'</span><span style="color: #800000;">11</span><span style="color: #800000;">'</span>,<span style="color: #800000;">'</span><span style="color: #800000;">WebSite</span><span style="color: #800000;">'</span>=><span style="color: #800000;">'</span><span style="color: #800000;">11</span><span style="color: #800000;">'</span><span style="color: #000000;">);$php_json </span>= json_encode($json_arr); <span style="color: #008000;">//</span><span style="color: #008000;">把php数组格式转换成 json 格式的数据</span>echo $php_json;