mb_ereg_replace_callback()

(PHP 5 >= 5.4.1, PHP 7)

Perform a regular expression search and replace with multibyte support using a callback

说明

mb_ereg_replace_callback(string $pattern,callable $callback,string $string[,string $option= "msr"]): string

Scans$stringfor matches to$pattern, then replaces the matched text with the output of$callbackfunction.

The behavior of this function is almost identical to mb_ereg_replace(), except for the fact that instead of$replacementparameter, one should specify a$callback.

参数

$pattern

The regular expression pattern.

Multibyte characters may be used in$pattern.

$callback

A callback that will be called and passed an array of matched elements in the$subjectstring. The callback should return the replacement string.

You'll often need the$callbackfunction for a mb_ereg_replace_callback() in just one place. In this case you can use an anonymous function to declare the callback within the call to mb_ereg_replace_callback(). By doing it this way you have all information for the call in one place and do not clutter the function namespace with a callback function's name not used anywhere else.

$string

The string being checked.

$option

The search option. See mb_regex_set_options() for explanation.

返回值

The resultant string on success, or FALSE on error.

注释

Note:

mb_regex_encoding()指定的内部编码或字符编码将会当作此函数用的字符编码。

范例

mb_ereg_replace_callback() example

<?php
// this text was used in 2002
// we want to get this up to date for 2003
$text = "April fools day is 04/01/2002\n";
$text.= "Last christmas was 12/24/2001\n";
// the callback function
function next_year($matches)
{
  // as usual: $matches[0] is the complete match
  // $matches[1] the match for the first subpattern
  // enclosed in '(...)' and so on
  return $matches[1].($matches[2]+1);
}
echo mb_ereg_replace_callback(
            "(\d{2}/\d{2}/)(\d{4})",
            "next_year",
            $text);
?>

以上例程会输出：

April fools day is 04/01/2003
Last christmas was 12/24/2002

mb_ereg_replace_callback() using anonymous function supported in PHP 5.3.0 or later

<?php
// this text was used in 2002
// we want to get this up to date for 2003
$text = "April fools day is 04/01/2002\n";
$text.= "Last christmas was 12/24/2001\n";
echo mb_ereg_replace_callback(
            "(\d{2}/\d{2}/)(\d{4})",
            function ($matches) {
               return $matches[1].($matches[2]+1);
            },
            $text);
?>

参见

• mb_regex_encoding()Set/Get character encoding for multibyte regex
• mb_ereg_replace()Replace regular expression with multibyte support
• Anonymous functions
• callback类型的信息