grapheme_substr()
(PHP 5 >= 5.3.0, PHP 7, PECL intl >= 1.0.0)
Return part of a string
说明
过程化风格
grapheme_substr(string $string,int $start[,int $length]): string
Return part of a string
参数
- $string
The input string. Must be valid UTF-8.
- $start
Start position in default grapheme units. If $start is non-negative, the returned string will start at the $start'th position in $string, counting from zero. If $start is negative, the returned string will start at the $start'th grapheme unit from the end of string.
- $length
Length in grapheme units. If $length is given and is positive, the string returned will contain at most $length grapheme units beginning from $start(depending on the length of string). If $length is given and is negative, then that many grapheme units will be omitted from the end of string(after the start position has been calculated when a start is negative). If $start denotes a position beyond this truncation,
FALSE
will be returned.
返回值
Returns the extracted part of $string.
更新日志
版本 | 说明 |
---|---|
5.4 | If$lengthis given and positive and the argument string is shorter than the specified length, all the rest of the string according to$startparameter is returned. Previously,FALSE was returned. |
范例
grapheme_substr() example
<?php $char_a_ring_nfd = "a\xCC\x8A"; // 'LATIN SMALL LETTER A WITH RING ABOVE' (U+00E5) normalization form "D" $char_o_diaeresis_nfd = "o\xCC\x88"; // 'LATIN SMALL LETTER O WITH DIAERESIS' (U+00F6) normalization form "D" print urlencode(grapheme_substr( "ao" . $char_a_ring_nfd . "bc" . $char_o_diaeresis_nfd . "O", 2, -1 )); ?>
以上例程会输出:
a%CC%8Abco%CC%88
参见
grapheme_extract()
Function to extract a sequence of default grapheme clusters from a text buffer, which must be encoded in UTF-8- » Unicode Text Segmentation: Grapheme Cluster Boundaries