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PHP Basics 2 Regular Expressions

Apr 26, 2018 pm 02:23 PM
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这篇文章介绍的内容是关于php的基础 ,有着一定的参考价值,现在分享给大家,有需要的朋友可以参考一下

<!-- PHP中的正则表达式 -->
<?php
//     定界符:
//     中间写正则
//     //
//     $$
//     %%
//     ^^
//     @@
//     ()
//     AA
//     include_once &#39;Class6.php&#39;;
    
    //原子通常指空格、点、特殊符号等;
//     特殊标识的原子
//   \d 匹配一个0-9
//   \D 除了0-9以外的所有字符
//   \w a-zA-Z0-9_
//   \W 除了0-9A-Za-z_以外的所有字符
//   \s 匹配所有空白字符\n\t\r空格
//   \S 匹配所有非空白字符
//   [] 指定范围的原子
    
    
    $zz = &#39;/a/&#39;;
    $string = &#39;fsadfgsadfasdfsd&#39;;
    if (preg_match($zz, $string,$matches)) {
        echo &#39;匹配到了,结果为:&#39;;
        var_dump($matches);
    }else{
        echo &#39;没有匹配到!&#39;;
    }
    
//     原子等价式
//     \w [a-zA-Z0-9_]
//     \W [^a-zA-Z0-9_]
//     \d [0-9]
//     \D [^0-9]
//     \s [\t\n\f\r]
//     \S [^\t\n\f\r]
    $zzz = &#39;/[^0-9A-Za-z_]/&#39;;
    $string = &#39;aaaaab311dd&#39;;
    $string1 = &#39;##@$#$%$%^^&#39;;
    if (preg_match($zzz, $string1,$matches)) {
        echo &#39;匹配成功,结果为:&#39;;
        var_dump($matches);
    }else{
        echo &#39;匹配失败!&#39;;
    }
    
    //元字符(重点)
    
    //模式匹配符
    $pattern = &#39;/^a\d+/m&#39;;
    $string3 = "学好成a9为大神,干番大事业";
    if (preg_match($pattern, $string3,$matches)) {
        echo &#39;匹配完成,结果为:&#39;;
        var_dump($matches);
    }else {
        echo &#39;匹配失败!&#39;.&#39;<br />&#39;;
    }
    
    $pattern = &#39;/新的未来.+\d+/s&#39;;
    $string = "新的未来987654321";
    if (preg_match($pattern, $string,$matches)) {
        echo &#39;匹配完成,结果为:&#39;;
        var_dump($matches);
    }else {
        echo &#39;匹配失败!&#39;;
    }
    
    $pattern = &#39;/(\w+)@(\w+).(com|org)/&#39;;
    $str = "bob@example.com";
    preg_match($pattern, $str, $match);
    print_r($match);
    
//     UBB文本编辑器
    $string4=&#39;[b]为你写诗句[/b]
    [i]为你做不可能的事[/i]
    [u]诶呀,哥不是写情诗[/u]
    [color=Red]哥是再说情歌[/color]
    [size=7]吴克群[/size]
    [qq]123123123[/qq]&#39;;
    //匹配UBB字符
    $pattern=array(
        &#39;/\[b\](.*)\[\/b\]i&#39;,
        &#39;/\[i\](.*)\[\/i\]iU&#39;,
        &#39;/\[u\](.*?)\[\/u\]/i&#39;,
        &#39;/\[color=(.*?)\](.*?)\[\/color\]/&#39;,
        &#39;/\[size=(\d)\](.*?)\[/\size\]/&#39;,
        &#39;/\[qq\](\d{5,12})\[\/qq\]&#39;
    );
    $replace=array(
        &#39;<b>\\1</b><br />&#39;,
        &#39;<i>\\1</i><br />&#39;,
        &#39;<u>\\1</u><br />&#39;,
        &#39;<font color="\\1">\\2</font><br />&#39;,
        &#39;<font size="\\1">\\2</font><br />&#39;,
        &#39;<a href="http://wpa.qq.com/msgrd?V=1&Uin
        =\\1&Site=[Discuz!]&Menu=yes"
        target="_blank"><img src="http://wpa.qq.com
        /pa?p=1:\\1:1" border="0"></a>&#39;,
    );
    $ubb = preg_replace($pattern, $replace, $string4);
    echo $ubb;
    
?>

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