php正则表达式例子汇总

<?php
    $title = "Replacement Canon BP-511 Camcorder Battery [Item ID:3-236-523]";
    if( eregi("([Item ID:)([0-9]+)-([0-9]+)-([0-9]+)(])",$title,$arr) ){
        echo "<pre class="brush:php;toolbar:false;">";
        print_r($arr);
        echo "

<?php
    // 分隔符可以是斜线，点，或横线
    $date = "04/30/1973";
    list($month, $day, $year) = split ('[/.-]', $date); // 漏洞: 04/30-1973也能匹配得上
    echo "Month: $month; Day: $day; Year: $year<br />
";
?>

<?phpif (preg_match ("/web/i", "PHP is the website scripting language of choice.")) {    print "A match was found.";} else {    print "A match was not found.";}?>

<?php
    // 从 URL 中取得主机名
    preg_match("/^(http://)?([^/]+)/i",
        "http://www.php.net/index.html", $matches);
    $host = $matches[2];
    // 从主机名中取得后面两段
    preg_match("/[^./]+.[^./]+$/", $host, $matches);
    echo "domain name is: {$matches[0]}
";
    // 本例执行后将输出: domain name is: php.net
?>

<?php
    preg_match_all ("|<[^>]+>(.*)</[^>]+>|U",
        "<b>example: </b><div align=left>this is a test</div>",
        $out, PREG_PATTERN_ORDER); // 注意PREG_PATTERN_ORDER和PREG_SET_ORDER的区别
    print $out[0][0].", ".$out[0][1]."
";
    print $out[1][0].", ".$out[1][1]."
";
    echo "<pre class="brush:php;toolbar:false;">";
    print_r($out);
?>

<?php
    $keywords = "$40 for a g3/400";
    $keywords = preg_quote ($keywords, "/");
    echo $keywords; // returns $40 for a g3/400
?>

<?php
    // 本例中，preg_quote($word) 用来使星号不在正则表达式中
    // 具有特殊含义。
    $textbody = "This book is *very* difficult to find.";
    $word = "*very*";
    $textbody = preg_replace ("/".preg_quote($word)."/","<b>".$word."</b>",$textbody);
    echo $textbody;
?>

<?php  
    // 此文本是用于 2002 年的，  
    // 现在想使其能用于 2003 年  
    $text = "April fools day is 04/01/2002
";  
    $text.= "Last christmas was 12/24/2001
";  
    // 回调函数  
    function next_year($matches) {    
    // 通常：$matches[0] 是完整的匹配项    
    // $matches[1] 是第一个括号中的子模式的匹配项    
    // 以此类推
      
     return $matches[1].($matches[2]+1);  
     }  
     echo preg_replace_callback("|(d{2}/d{2}/)(d{4})|","next_year",$text);  
     // 结果为：  
     // April fools day is 04/01/2003  
     // Last christmas was 12/24/2002
 ?>

<?php
    $string = "The quick brown fox jumped over the lazy dog.";
    $patterns[0] = "/quick/";
    $patterns[1] = "/brown/";
    $patterns[2] = "/fox/";
    $replacements[2] = "bear";
    $replacements[1] = "black";
    $replacements[0] = "slow";
    print preg_replace($patterns, $replacements, $string);
    /* Output
        ======
    The bear black slow jumped over the lazy dog.
    */
    /* By ksorting patterns and replacements,
        we should get what we wanted. */
    ksort($patterns);
    ksort($replacements);
    print preg_replace($patterns, $replacements, $string);
    /* Output
        ======
    The slow black bear jumped over the lazy dog.
    */
?>

<?php
    // $document 应包含一个 HTML 文档。
    // 本例将去掉 HTML 标记，# 代码
    // 和空白字符。还会将一些通用的
    // HTML 实体转换成相应的文本。
    $search = array ("'<script[^>]*?>.*?</script>'si", // 去掉 #
                     "'<[/!]*?[^<>]*?>'si", // 去掉 HTML 标记
                     "'([
])[s]+'", // 去掉空白字符
                     "'&(quot|#34);'i", // 替换 HTML 实体
                     "'&(amp|#38);'i",
                     "'&(lt|#60);'i",
                     "'&(gt|#62);'i",
                     "'&(nbsp|#160);'i",
                     "'&(iexcl|#161);'i",
                     "'&(cent|#162);'i",
                     "'&(pound|#163);'i",
                     "'&(copy|#169);'i",
                     "'&#(d+);'e"); // 作为 PHP 代码运行
    $replace = array ("",
                      "",
                      "\1",
                      """,
                      "&",
                      "<",
                      ">",
                      " ",
                       chr(161),
                       chr(162),
                       chr(163),
                       chr(169),
                      "chr(\1)");
    $text = preg_replace ($search, $replace, $document);
?>