php正则preg_replace_callback函数用法实例

本文实例讲述了php正则preg_replace_callback函数的用法。分享给大家供大家参考。具体实现方法

本文实例讲述了php正则preg_replace_callback函数的用法。分享给大家供大家参考。具体实现方法如下：

php正则表达式功能强大，本范例演示了preg_replace_callback函数的用法

// Define a dummy text, for testing...
$Text = "Title: Hello world!\n";
$Text .= "Author: Jonas\n";
$Text .= "This is a example message!\n\n";
$Text .= "Title: Entry 2\n";
$Text .= "Author: Sonja\n";
$Text .= "Hello world, what's up!\n";
// This function will replace specific matches
// into a new form
function RewriteText($Match){
 // Entire matched section: 
 // --> /.../
 $EntireSection = $Match[0];
 // --> "\nTitle: Hello world!"
 // Key 
 // --> ([a-z0-9]+)
 $Key = $Match[1];
 // --> "Title"
 // Value 
 // --> ([^\n\r]+)
 $Value = $Match[2];
 // --> "Hello world!"
 // Add some bold (<b>) tags to around the key to
 return '<b>' . $Key . '</b>: ' . $Value;
}
// The regular expression will extract and pass all "key: value" pairs to
// the "RewriteText" function that is definied above
$NewText = preg_replace_callback('/[\r\n]([a-z0-9]+): ([^\n\r]+)/i', "RewriteText", $Text);
// Print the new modified text
print $NewText;

希望本文所述对大家的php程序设计有所帮助。