mb_ereg_search_pos

Function name: mb_ereg_search_pos()

Applicable version: PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8

Usage: The mb_ereg_search_pos() function is used to search for matching substrings in multibyte strings and return their position. This function is part of the mb_ereg_search() function and is used with the mb_ereg_search_init() and mb_ereg_search_regs() functions.

Syntax: mb_ereg_search_pos(string $pattern, string $option = 'ms')

parameter:

• pattern: The regular expression pattern to search for.
• option: Optional parameter, option to set regular expressions. The default is 'ms', which means multi-line mode and single-byte mode. Other valid options include 'm' (multi-line mode), 'i' (case insensitive), 'x' (comments allowed), 's' (single byte mode), 'U' (non-greedy mode).

Return value: If a matching substring is found, a two-element array is returned, containing the start and end positions of the matching substring. If no matching substring is found, false is returned.

Example:

 $text = "你好，世界！Hello, World!"; $pattern = '世界'; if (mb_ereg_search_init($text, $pattern)) { $pos = mb_ereg_search_pos(); if ($pos !== false) { echo "找到匹配的子字符串："; echo "起始位置：" . $pos[0] . "，结束位置：" . $pos[1]; } else { echo "未找到匹配的子字符串。"; } } else { echo "正则表达式初始化失败。"; }

Output:

找到匹配的子字符串：起始位置：9，结束位置：11

In the above example, we first call the mb_ereg_search_init() function to initialize the regular expression search, and then call the mb_ereg_search_pos() function to get the position of the matching substring. Finally, judge whether a matching substring is found based on the return value and output the corresponding result.