stripos

(PHP 5)

stripos — 查找字符串首次出现的位置（不区分大小写）

说明

int stripos ( string $haystack , string $needle [, int $offset = 0 ] )

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 参数允许你指定从 haystack 中的哪个字符开始查找。返回的位置数字值仍然相对于 haystack 的起始位置。

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 。

Warning

此函数可能返回布尔值 FALSE ，但也可能返回等同于 FALSE 的非布尔值。请阅读布尔类型章节以获取更多信息。应使用 === 运算符来测试此函数的返回值。

范例

Example #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

Note: 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

用户评论:

[#1] Ian Macdonald [2015-08-29 10:25:57]

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.

[#2] spam at kleppinger dot com [2015-03-04 14:08:11]

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.

[#3] spam at wikicms dot org [2013-12-15 08:57:32]

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 ?>

[#4] steve at opilo dot net [2013-07-01 16:38:03]

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; } ?>

[#5] emperorshishire at gmail dot com [2009-02-24 19:31:52]

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)); ?>

[#6] grf at post dot cz [2007-03-20 04:57:59]

this would to work with any language, i hope.
tested on czech (eastern europe) lang.

<?php 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() ?>