PHP5中文手册·Find position of last occurrence of a char in a string -- 追寻梦想＞编程乐园＞PHP 编程

说明

int strrpos ( string $haystack , string $needle [, int $offset ] )

Returns the numeric position of the last occurrence of needle in the haystack string. Note that the needle in this case can only be a single character in PHP 4. If a string is passed as the needle, then only the first character of that string will be used.

If needle is not found, returns FALSE.

It is easy to mistake the return values for "character found at position 0" and "character not found". Here's how to detect the difference:


<?php

// in PHP 4.0.0 and newer:
$pos = strrpos($mystring, "b");
if ($pos === false) { // note: three equal signs
    // not found...
}

// in versions older than 4.0.0:
$pos = strrpos($mystring, "b");
if (is_bool($pos) && !$pos) {
    // not found...
}
?>

If needle is not a string, it is converted to an integer and applied as the ordinal value of a character.

Note: As of PHP 5.0.0 offset may be specified to begin searching an arbitrary number of characters into the string. Negative values will stop searching at an arbitrary point prior to the end of the string.

Note: The needle may be a string of more than one character as of PHP 5.0.0.

参数

haystack
needle
offset

strrpos

说明

参数

返回值

参见


	PHP5中文手册 strripos strspn Strings PHP Manual strrpos (PHP 4, PHP 5) strrpos — Find position of last occurrence of a char in a string 说明 int strrpos ( string `$haystack` , string `$needle` [, int `$offset` ] ) Returns the numeric position of the last occurrence of `needle` in the `haystack` string. Note that the needle in this case can only be a single character in PHP 4. If a string is passed as the needle, then only the first character of that string will be used. If `needle` is not found, returns `FALSE`. It is easy to mistake the return values for "character found at position 0" and "character not found". Here's how to detect the difference: `<?php // in PHP 4.0.0 and newer: $pos = strrpos($mystring, "b"); if ($pos === false) { // note: three equal signs // not found... } // in versions older than 4.0.0: $pos = strrpos($mystring, "b"); if (is_bool($pos) && !$pos) { // not found... } ?>` If `needle` is not a string, it is converted to an integer and applied as the ordinal value of a character. Note: As of PHP 5.0.0 `offset` may be specified to begin searching an arbitrary number of characters into the string. Negative values will stop searching at an arbitrary point prior to the end of the string. Note: The `needle` may be a string of more than one character as of PHP 5.0.0. 参数 `haystack` `needle` `offset` 返回值参见 strpos() strripos() strrchr() substr() stristr() strstr() strripos strspn Strings PHP Manual