stripos
(PHP 5, PHP 7, PHP 8)
stripos — 查找字符串首次出现的位置（不区分大小写）
说明
stripos(string
$haystack, string $needle, int $offset = 0): int
返回在字符串 haystack 中 needle 首次出现的数字位置。
与 strpos() 不同，stripos() 不区分大小写。
参数
-
haystack -
在该字符串中查找。
-
needle -
注意
needle可以是一个单字符或者多字符的字符串。如果
needle不是一个字符串，那么它将被转换为整型并被视为字符顺序值。 -
offset -
可选的
offset参数，从字符此数量的开始位置进行搜索。 如果是负数，就从字符末尾此数量的字符数开始统计。
返回值
返回 needle 存在于 haystack 字符串开始的位置(独立于偏移量)。同时注意字符串位置起始于 0，而不是 1。
如果未发现 needle 将返回 false。
更新日志
| 版本 | 说明 |
|---|---|
| 7.1.0 |
开始支持负数的 offset。
|
范例
示例 #1 stripos() 范例
<?php
$findme = 'a';
$mystring1 = 'xyz';
$mystring2 = 'ABC';
$pos1 = stripos($mystring1, $findme);
$pos2 = stripos($mystring2, $findme);
// 'a' 当然不在 'xyz' 中
if ($pos1 === false) {
echo "The string '$findme' was not found in the string '$mystring1'";
}
// 注意这里使用的是 ===。简单的 == 不能像我们期望的那样工作，
// 因为 'a' 的位置是 0（第一个字符）。
if ($pos2 !== false) {
echo "We found '$findme' in '$mystring2' at position $pos2";
}
?>
注释
注意: 此函数可安全用于二进制对象。
参见
- mb_stripos() - 大小写不敏感地查找字符串在另一个字符串中首次出现的位置
- strpos() - 查找字符串首次出现的位置
- strrpos() - 计算指定字符串在目标字符串中最后一次出现的位置
- strripos() - 计算指定字符串在目标字符串中最后一次出现的位置（不区分大小写）
- stristr() - strstr 函数的忽略大小写版本
- substr() - 返回字符串的子串
- str_ireplace() - str_replace 的忽略大小写版本
add a note
User Contributed Notes 8 notes
emperorshishire at gmail dot com ¶
13 years ago
I found myself needing to find the first position of multiple needles in one haystack. So I wrote this little function:
<?php
function multineedle_stripos($haystack, $needles, $offset=0) {
foreach($needles as $needle) {
$found[$needle] = stripos($haystack, $needle, $offset);
}
return $found;
}
// It works as such:
$haystack = "The quick brown fox jumps over the lazy dog.";
$needle = array("fox", "dog", ".", "duck")
var_dump(multineedle_stripos($haystack, $needle));
/* Output:
array(3) {
["fox"]=>
int(16)
["dog"]=>
int(40)
["."]=>
int(43)
["duck"]=>
bool(false)
}
*/
?>
sorrynorealemail at example dot com ¶
3 years ago
Unlike strpos() it seems that stripos() does NOT issue a WARNING if the needle is an empty string ''.
emanuel dot karlsson at rolfsbuss dot se ¶
3 years ago
Finding numbers in strings requires you to cast the number to string first.
strpos("123", 2) !== strpos("123", "2")
spam at kleppinger dot com ¶
7 years ago
Regarding the function by spam at wikicms dot org
It is very bad practice to use the same function name as an existing php function but have a different output format. Someone maintaining the code in the future is likely to be very confused by this. It will also be hard to eradicate from a codebase because the naming is identical so each use of stripos() would have to be analyzed to see how it is expecting the output format (bool or number/bool).
Calling it string_found() or something like that would make a lot more sense for long-term use.
Ian Macdonald ¶
6 years ago
Regarding the === note, it might be worth clarifying that the correct tests for a binary found/not found condition are !==false to detect found, and ===false to detect not found.
steve at opilo dot net ¶
8 years ago
A handy function if you need to adjust layout based on whether or not a string contains descending letters:
<?php function containsDescenders($text) {
$descenders = array("g","j","p","q","y");
foreach ($descenders as $letter) {
if (stripos($text,$letter) !== false) {
return true;
}
}
return false;
} ?>
spam at wikicms dot org ¶
8 years ago
If you like using ternary operator, I wrote simple example how to use stripos function.
Also, in my example I add "How to use namespaces" for wide knowledges for newbies.
<?php
namespace My;
//You can be free using core functions in your NameSpaces (My)
function stripos($haystack, $needle) {
//To call core function (from global NS) you should add backslash only - \func
return (FALSE === \stripos($haystack, $needle)) ? FALSE : TRUE;
}
var_dump(stripos($haystack = 'John knows English language.', $needle = 'john')); //TRUE
var_dump(stripos($haystack = 'Sara knows English language too.', $needle = 'john')); //FALSE
?>
grf at post dot cz ¶
15 years ago
this would to work with any language, i hope.
tested on czech (eastern europe) lang.
<?php
/****************************************
* SAFE HIGHLIGHT
****************************************/
/**
* function finds and encase every string in a $needleArr array with
* strings $shearLft (from the left side) and $shearRgt (guess from which
* side).
* already encased needles are IGNORED for any other step, so order
* of needles in $needleArr is pretty important.
*
* function is searching needles in case-insensitive mode,
* but case in the subject is saved.
*
* can you do it better? so, do it.
*
* @param array $needleArr array of needles
* @param string $shearLft left shear
* @param string $shearRgt right shear
* @param string $subject subject
* @param string $encoding encoding ('utf-8' is default)
*
* @author griffin
*/
function safeHighlight( $needleArr, $shearLft, $shearRgt, $subject, $encoding = 'utf-8')
{
// encoding
$e = $encoding;
// oh, no needles
if( !is_array( $needleArr))
return $subject;
// empty keys throw-off, only unique, reindex
$nA = array_values(
array_unique(
array_diff( $needleArr, array(''))
)
);
// needle count
if( !($nC = count( $nA)))
return $subject; // nothing to hl
// shear length
if( !(($rLL = mb_strlen( $rL = $shearLft, $e))
+ ($rRL = mb_strlen( $rR = $shearRgt, $e))))
return $subject; // no shears
// subject length
if( !($sL = mb_strlen( $s = $subject, $e)))
return null; // empty subject
// subject in lowercase (we need to aviod
// using mb_stripos due to PHP version)
$sW = mb_strtolower( $s, $e);
// masking ~ 0=not changed, 1=changed
$m = str_repeat( '0', $sL);
// loop for each needle
for( $n=0; $n<$nC; $n++)
{
// needle string loWercase
$nW = mb_strtolower( $nA[ $n], $e);
$o = 0; // offset
$nL = mb_strlen( $nW, $e); // needle length
// search needle
while( false !== ($p = mb_strpos( $sW, $nW, $o, $e)))
{
// oh hurrey, needle found on $p position
// is founded needle already modified? (in full-length)
for( $q=$p; $q<($p+$nL); $q++)
if( $m[ $q])
{
// ai, caramba. already modified, jump over
$o+= $nL;
// continue for while() loop - not for for() loop!
continue 2;
}
// explode subject and mask into three parts
// partA|needle|partB
$sE[0] = mb_substr( $s, 0, $p, $e);
$sE[1] = mb_substr( $s, $p, $nL, $e);
$sE[2] = mb_substr( $s, $p+$nL, $sL-$p-$nL, $e);
// mask
// partA|partB (needle not needed)
$mE[0] = mb_substr( $m, 0, $p, $e);
$mE[1] = mb_substr( $m, $p+$nL, $sL-$p-$nL, $e);
// apply shears
$sE[1] = $rL.$sE[1].$rR;
// update sunject length
$sL+= $rLL + $rRL;
// update mask
$m = $mE[0] . str_repeat( '1', $rLL + $nL + $rRL) . $mE[1];
// implode into a subject
$s = implode( $sE);
// update lowercase subject
$sW = mb_strtolower( $s, $e);
// increase offset
$o+= $rLL + $nL + $rRL;
// end of string reached
if( $o>=$sL)
break;
} // while()
} // for( $n=0; $n<$nC; $n++)
// oouu yeaaa, kick the subject out of the function
return $s;
} // function safeHighlight()
/****************************************
* END: SAFE HIGHLIGHT
****************************************/
?>