php实现简单的语法高亮函数实例分析

本文实例讲述了php实现简单的语法高亮函数。分享给大家供大家参考。具体分析如下：

这是一个php实现的简单语法高亮显示的函数，注意：这个函数设计的比较简单，可能对某些语法不能高亮显示，你可以自己扩充该函数的功能

    function syntax_highlight($code){
     // this matches --> "foobar" <--
     $code = preg_replace(
      '/"(.*?)"/U', 
      '"<span style="color: #007F00">$1</span>"', $code
     );
     // hightlight functions and other structures like --> function foobar() <--- 
     $code = preg_replace(
      '/(\s)\b(.*?)((\b|\s)\()/U', 
      '$1<span style="color: #0000ff">$2</span>$3', 
      $code
     );
     // Match comments (like /* */): 
     $code = preg_replace(
      '/(\/\/)(.+)\s/', 
      '<span style="color: #660066; background-color: #FFFCB1;"><i>$0</i></span>', 
      $code
     );
     $code = preg_replace(
      '/(\/\*.*?\*\/)/s', 
      '<span style="color: #660066; background-color: #FFFCB1;"><i>$0</i></span>', 
      $code
     );
     // hightlight braces:
     $code = preg_replace('/(\(|\[|\{|\}|\]|\)|\->)/', '<strong>$1</strong>', $code);
     // hightlight variables $foobar
     $code = preg_replace(
      '/(\$[a-zA-Z0-9_]+)/', '<span style="color: #0000B3">$1</span>', $code
     );
     /* The \b in the pattern indicates a word boundary, so only the distinct
     ** word "web" is matched, and not a word partial like "webbing" or "cobweb" 
     */
     // special words and functions
     $code = preg_replace(
      '/\b(print|echo|new|function)\b/', 
      '<span style="color: #7F007F">$1</span>', $code
     );
     return $code;
    }
    /*example-start*/
    /*
    ** Create some example PHP code:
    */
    $example_php_code = '
    // some code comment:
    $example = "foobar";
    print $_SERVER["REMOTE_ADDR"];
    $array = array(1, 2, 3, 4, 5);
    function example_function($str) {
     // reverse string
     echo strrev($obj);
    }
    print example_function("foo");
    /*
    ** A multiple line comment
    */
    print "Something: " . $example;';
    // output the formatted code:
    print '<pre>';
    print syntax_highlight($example_php_code);
    print '</pre>';
    /*example-end*/

希望本文所述对大家的php程序设计有所帮助。