php给一组指定关键词添加span标签的方法

本文实例讲述了php给一组指定关键词添加span标签的方法。分享给大家供大家参考。具体如下：

这里是php给一组指定的关键词添加span标签，高亮突出显示关键词

// example use: $spanned = codewords($string_containing_keywords);
// my site: andrew.dx.am
// using colour==blue, but different arrays of words and different 
// colours can be added.
function onlywholewords(&$value, $key) {
// ignores words after // comment delimiters.
//$value = "/\b(" . $value . ")\b/";  // doesn't handle comments
//$value = "/^(?:(?!\/\/).)*\k\b(" . $value . ")\b/"; 
// \k lookbehind alternative is not supported in php < 5.2.4, so use:
  $value = "/^((?:(?!\/\/).)*)\b" . $value . "\b/";
}
function addspan(&$value, $key, $color='blue') {
  $value = "$1<span style='color:$color'>" . $value . "</span>";
}
function codewords($code) {
  $keywords = array('as', 'break', 'case', 'class',
  'continue', 'default', 'do', 'elif', 'else',
  'elseif', 'for', 'foreach', 'function', 'if', 
  'new', 'null', 'return', 'self', 'switch',
  'this', 'to', 'typeof', 'until',
  'var', 'void', 'while', 'with');
  $keywords2 = $keywords;
  array_walk($keywords, 'onlywholewords');
  array_walk($keywords2, 'addspan', 'blue');
  $code = preg_replace($keywords, $keywords2, $code);
  return $code;
}

希望本文所述对大家的php程序设计有所帮助。