5.5.15

String 関数

参考

より強力な文字列処理および処理関数については、 POSIX 正規表現関数および Perl 互換正規表現関数 を参照ください。

目次

  • addcslashes — C 言語と同様にスラッシュで文字列をクォートする
  • addslashes — 文字列をスラッシュでクォートする
  • bin2hex — バイナリのデータを16進表現に変換する
  • chop — rtrim のエイリアス
  • chr — 特定の文字を返す
  • chunk_split — 文字列をより小さな部分に分割する
  • convert_cyr_string — キリル文字セットを他のものに変換する
  • convert_uudecode — uuencode された文字列をデコードする
  • convert_uuencode — 文字列を uuencode する
  • count_chars — 文字列で使用されている文字に関する情報を返す
  • crc32 — 文字列の crc32 多項式計算を行う
  • crypt — 文字列の一方向のハッシュ化を行う
  • echo — 1 つ以上の文字列を出力する
  • explode — 文字列を文字列により分割する
  • fprintf — フォーマットされた文字列をストリームに書き込む
  • get_html_translation_table — htmlspecialchars および htmlentities で使用される変換テーブルを返す
  • hebrev — 論理表記のヘブライ語を物理表記に変換する
  • hebrevc — 論理表記のヘブライ語を、改行の変換も含めて物理表記に変換する
  • hex2bin — 16進エンコードされたバイナリ文字列をデコードする
  • html_entity_decode — HTML エンティティを適切な文字に変換する
  • htmlentities — 適用可能な文字を全て HTML エンティティに変換する
  • htmlspecialchars_decode — 特殊な HTML エンティティを文字に戻す
  • htmlspecialchars — 特殊文字を HTML エンティティに変換する
  • implode — 配列要素を文字列により連結する
  • join — implode のエイリアス
  • lcfirst — 文字列の最初の文字を小文字にする
  • levenshtein — 二つの文字列のレーベンシュタイン距離を計算する
  • localeconv — 数値に関するフォーマット情報を得る
  • ltrim — 文字列の最初から空白 (もしくはその他の文字) を取り除く
  • md5_file — 指定したファイルのMD5ハッシュ値を計算する
  • md5 — 文字列のmd5ハッシュ値を計算する
  • metaphone — 文字列の metaphone キーを計算する
  • money_format — 数値を金額文字列にフォーマットする
  • nl_langinfo — 言語およびロケール情報を検索する
  • nl2br — 改行文字の前に HTML の改行タグを挿入する
  • number_format — 数字を千位毎にグループ化してフォーマットする
  • ord — 文字の ASCII 値を返す
  • parse_str — 文字列を処理し、変数に代入する
  • print — 文字列を出力する
  • printf — フォーマット済みの文字列を出力する
  • quoted_printable_decode — quoted-printable 文字列を 8 ビット文字列に変換する
  • quoted_printable_encode — 8 ビット文字列を quoted-printable 文字列に変換する
  • quotemeta — メタ文字をクォートする
  • rtrim — 文字列の最後から空白 (もしくはその他の文字) を取り除く
  • setlocale — ロケール情報を設定する
  • sha1_file — ファイルの sha1 ハッシュを計算する
  • sha1 — 文字列の sha1 ハッシュを計算する
  • similar_text — 二つの文字列の間の類似性を計算する
  • soundex — 文字列の soundex キーを計算する
  • sprintf — フォーマットされた文字列を返す
  • sscanf — フォーマット文字列に基づき入力を処理する
  • str_getcsv — CSV 文字列をパースして配列に格納する
  • str_ireplace — 大文字小文字を区別しない str_replace
  • str_pad — 文字列を固定長の他の文字列で埋める
  • str_repeat — 文字列を反復する
  • str_replace — 検索文字列に一致したすべての文字列を置換する
  • str_rot13 — 文字列に rot13 変換を行う
  • str_shuffle — 文字列をランダムにシャッフルする
  • str_split — 文字列を配列に変換する
  • str_word_count — 文字列に使用されている単語についての情報を返す
  • strcasecmp — 大文字小文字を区別しないバイナリセーフな文字列比較を行う
  • strchr — strstr のエイリアス
  • strcmp — バイナリセーフな文字列比較
  • strcoll — ロケールに基づく文字列比較
  • strcspn — マスクにマッチしない最初のセグメントの長さを返す
  • strip_tags — 文字列から HTML および PHP タグを取り除く
  • stripcslashes — addcslashes でクォートされた文字列をアンクォートする
  • stripos — 大文字小文字を区別せずに文字列が最初に現れる位置を探す
  • stripslashes — クォートされた文字列のクォート部分を取り除く
  • stristr — 大文字小文字を区別しない strstr
  • strlen — 文字列の長さを得る
  • strnatcasecmp — "自然順"アルゴリズムにより大文字小文字を区別しない文字列比較を行う
  • strnatcmp — "自然順"アルゴリズムにより文字列比較を行う
  • strncasecmp — バイナリセーフで大文字小文字を区別しない文字列比較を、最初の n 文字について行う
  • strncmp — 最初の n 文字についてバイナリセーフな文字列比較を行う
  • strpbrk — 文字列の中から任意の文字を探す
  • strpos — 文字列内の部分文字列が最初に現れる場所を見つける
  • strrchr — 文字列中に文字が最後に現れる場所を取得する
  • strrev — 文字列を逆順にする
  • strripos — 文字列中で、特定の(大文字小文字を区別しない)文字列が最後に現れた位置を探す
  • strrpos — 文字列中に、ある部分文字列が最後に現れる場所を探す
  • strspn — 指定したマスク内に含まれる文字からなる文字列の最初のセグメントの長さを探す
  • strstr — 文字列が最初に現れる位置を見つける
  • strtok — 文字列をトークンに分割する
  • strtolower — 文字列を小文字にする
  • strtoupper — 文字列を大文字にする
  • strtr — 文字の変換あるいは部分文字列の置換を行う
  • substr_compare — 指定した位置から指定した長さの 2 つの文字列について、バイナリ対応で比較する
  • substr_count — 副文字列の出現回数を数える
  • substr_replace — 文字列の一部を置換する
  • substr — 文字列の一部分を返す
  • trim — 文字列の先頭および末尾にあるホワイトスペースを取り除く
  • ucfirst — 文字列の最初の文字を大文字にする
  • ucwords — 文字列の各単語の最初の文字を大文字にする
  • vfprintf — フォーマットされた文字列をストリームに書き込む
  • vprintf — フォーマットされた文字列を出力する
  • vsprintf — フォーマットされた文字列を返す
  • wordwrap — 指定した文字数で文字列を分割する
add a note add a note

User Contributed Notes 24 notes

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2
admin at fivestarbuy dot com
8 years ago
This example lets you parse an unparsed strings variables. Warning: This could cause security leaks if you allow users to pass $variables through this engine. I recommend only using this for your Content Management System.

<?
$mytime=time();
$mydog="My Dog Ate My PHP!";

# Your Parsing String:
$s1 = 'Hyphen Variable Preserving: $mytime, and $mydog';
echo "Before: <br><br>$s1<br><br>";

# Remember, wherever you define this, it will not be defined GLOBAL into the function
# which is why we define it here. Defining it global could lead to security issues.
$vardata=get_defined_vars();

# Parse the string
$s1 = StrParse($s1,$vardata);

echo "After: <br><br>$s1";

function StrParse($str,$vardata) {
# Takes a string, or piece of data, that contains PHP Variables

# For example, unparsed variables like:  Test using time: $mytime
# This example shows $mytime, and not the actual variable value.
# The end result shows the actual variable value of $mytime.

# This is useful for building a content management system,
# and directing your variables into your content data,
# where content is stored in a file or database, unparsed.
# Of course this could slow down page loads, but it's a good way
# to parse data from current variables into your loaded new data
# making it compatible.

# Then the variables are replaced with the actual variable..
$getvarkeys=array_keys($vardata);
$ret=$str;
for ($x=0; $x < count($getvarkeys); $x++) {
    $myvar=$getvarkeys[$x];
    #echo "Variable: " . $myvar . " [" . $vardata[$myvar] . "]<br>";
    $ret=str_replace('$' . $myvar, $vardata[$myvar], $ret);
}
return $ret;

}

?>
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1
webmaster at cafe-clope dot net
8 years ago
A comprehensive concatenation function, that works with array and strings

<?php
function str_cat() {
 
$args = func_get_args() ;
   
 
// Asserts that every array given as argument is $dim-size.
  // Keys in arrays are stripped off.
  // If no array is found, $dim stays unset.
 
foreach($args as $key => $arg) {
    if(
is_array($arg)) {
      if(!isset(
$dim))
       
$dim = count($arg) ;
      elseif(
$dim != count($arg))
        return
FALSE ;
     
$args[$key] = array_values($arg) ;
    }
  }
       
 
// Concatenation
 
if(isset($dim)) {
   
$result = array() ;
    for(
$i=0;$i<$dim;$i++) {
     
$result[$i] = '' ;
      foreach(
$args as $arg)
       
$result[$i] .= ( is_array($arg) ? $arg[$i] : $arg ) ;
    }
    return
$result ;
  } else {
    return
implode($args) ;
  }
}
?>

A simple example :

<?php
str_cat
(array(1,2,3), '-', array('foo' => 'foo', 'bar' => 'bar', 'noop' => 'noop')) ;
?>

will return :
Array (
  [0] => 1-foo
  [1] => 2-bar
  [2] => 3-noop
)

More usefull :

<?php
$myget
= $_GET ; // retrieving previous $_GET values
$myget['foo'] = 'b a r' ; // changing one value
$myget = str_cat(array_keys($myget), '=', array_map('rawurlencode', array_values($myget))) ;
$querystring = implode(ini_get('arg_separator.output'), $myget)) ;
?>

will return a valid querystring with some values changed.

Note that <?php str_cat('foo', '&', 'bar') ; ?> will return 'foo&bar', while <?php str_cat(array('foo'), '&', 'bar') ; ?> will return array(0 => foo&bar)
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1
kristin at greenapple dot on dot ca
9 years ago
I really searched for a function that would do this as I've seen it in other languages but I couldn't find it here. This is particularily useful when combined with substr() to take the first part of a string up to a certain point.

strnpos() - Find the nth position of needle in haystack.

<?php

   
function strnpos($haystack, $needle, $occurance, $pos = 0) {
       
        for (
$i = 1; $i <= $occurance; $i++) {
           
$pos = strpos($haystack, $needle, $pos) + 1;
        }
        return
$pos - 1;
       
    }

?>

Example: Give me everything up to the fourth occurance of '/'.

<?php

    $haystack
= "/home/username/www/index.php";
   
$needle = "/";
   
   
$root_dir = substr($haystack, 0, strnpos($haystack, $needle, 4));
   
    echo
$root_dir;
   
?>

Returns: /home/username/www

Use this example with the server variable $_SERVER['SCRIPT_NAME'] as the haystack and you can self-discover a document's root directory for the purposes of locating global files automatically!
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0
str at maphpia dot com
1 year ago
I was looking for a function to find the common substring in 2 different strings. I tried both the mb_string_intersect and string_intersect functions listed here but didn't work for me. I found the algorithm at http://en.wikibooks.org/wiki/Algorithm_implementation/Strings/Longest_common_substring#PHP so here I post you the function

<?php

/**
* Finds the matching string between 2 strings
*
* @param string $string1
* @param string $string2
* @param number $minChars
*
* @return NULL|string
*
* @link http://en.wikibooks.org/wiki/Algorithm_implementation/Strings/Longest_common_substring#PHP
*/
function string_intersect($string_1, $string_2)
{
   
$string_1_length = strlen($string_1);
   
$string_2_length = strlen($string_2);
   
$return          = "";

    if (
$string_1_length === 0 || $string_2_length === 0) {
       
// No similarities
       
return $return;
    }

   
$longest_common_subsequence = array();

   
// Initialize the CSL array to assume there are no similarities
   
for ($i = 0; $i < $string_1_length; $i++) {
       
$longest_common_subsequence[$i] = array();
        for (
$j = 0; $j < $string_2_length; $j++) {
           
$longest_common_subsequence[$i][$j] = 0;
        }
    }

   
$largest_size = 0;

    for (
$i = 0; $i < $string_1_length; $i++) {
        for (
$j = 0; $j < $string_2_length; $j++) {
           
// Check every combination of characters
           
if ($string_1[$i] === $string_2[$j]) {
               
// These are the same in both strings
               
if ($i === 0 || $j === 0) {
                   
// It's the first character, so it's clearly only 1 character long
                   
$longest_common_subsequence[$i][$j] = 1;
                } else {
                   
// It's one character longer than the string from the previous character
                   
$longest_common_subsequence[$i][$j] = $longest_common_subsequence[$i - 1][$j - 1] + 1;
                }

                if (
$longest_common_subsequence[$i][$j] > $largest_size) {
                   
// Remember this as the largest
                   
$largest_size = $longest_common_subsequence[$i][$j];
                   
// Wipe any previous results
                   
$return       = "";
                   
// And then fall through to remember this new value
               
}

                if (
$longest_common_subsequence[$i][$j] === $largest_size) {
                   
// Remember the largest string(s)
                   
$return = substr($string_1, $i - $largest_size + 1, $largest_size);
                }
            }
           
// Else, $CSL should be set to 0, which it was already initialized to
       
}
    }

   
// Return the list of matches
   
return $return;
}
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0
navarr at gmail dot com
8 years ago
stripos for PHP4.x

<?php
 
function stripos($haystack,$needle) {
    return
strpos(strtoupper($haystack),strtoupper($needle));
  }
?>
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0
t0russ at gmail dot com
9 years ago
to kristin at greenaple dot on dot ca:
thanx for sharing.
your function in recursive form proved to be slightly faster and it returns false (as it should) when the character is not found instead of number 0:
<?php
function strnposr($haystack, $needle, $occurance, $pos = 0) {
    return (
$occurance<2)?strpos($haystack, $needle, $pos):strnposr($haystack,$needle,$occurance-1,strpos($haystack, $needle, $pos) + 1);
}
?>
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0
james dot d dot baker at gmail dot com
9 years ago
<?php
/*
Written By James Baker, May 27th 2005

sentenceCase($string);
    $string: The string to convert to sentence case.

Converts a string into proper sentence case (First letter of each sentance capital, all the others smaller)

Example Usage:
echo sentenceCase("HELLO WORLD!!! THIS IS A CAPITALISED SENTENCE. this isn't.");

Returns:
Hello world!!! This is a capitalised sentence. This isn't.
*/

function sentenceCase($s){
   
$str = strtolower($s);
   
$cap = true;
   
    for(
$x = 0; $x < strlen($str); $x++){
       
$letter = substr($str, $x, 1);
        if(
$letter == "." || $letter == "!" || $letter == "?"){
           
$cap = true;
        }elseif(
$letter != " " && $cap == true){
           
$letter = strtoupper($letter);
           
$cap = false;
        }
       
       
$ret .= $letter;
    }
   
    return
$ret;
}
?>
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0
Anonymous
9 years ago
In response to hackajar <matt> yahoo <trot> com,

No string-to-array function exists because it is not needed. If you reference a string with an offset like you do with an array, the character at that offset will be return. This is documented in section III.11's "Strings" article under the "String access and modification by character" heading.
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0
andy a t onesandzeros d o t biz
9 years ago
I use these little doo-dads quite a bit. I just thought I'd share them and maybe save someone a little time. No biggy. :)

// returns true if $str begins with $sub
function beginsWith( $str, $sub ) {
    return ( substr( $str, 0, strlen( $sub ) ) == $sub );
}

// return tru if $str ends with $sub
function endsWith( $str, $sub ) {
    return ( substr( $str, strlen( $str ) - strlen( $sub ) ) == $sub );
}

// trims off x chars from the front of a string
// or the matching string in $off is trimmed off
function trimOffFront( $off, $str ) {
    if( is_numeric( $off ) )
        return substr( $str, $off );
    else
        return substr( $str, strlen( $off ) );
}

// trims off x chars from the end of a string
// or the matching string in $off is trimmed off
function trimOffEnd( $off, $str ) {
    if( is_numeric( $off ) )
        return substr( $str, 0, strlen( $str ) - $off );
    else
        return substr( $str, 0, strlen( $str ) - strlen( $off ) );
}
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0
[tab!]
9 years ago
//
// string strtrmvistl(  string str, [int maxlen = 64],
//                      [bool right_justify = false],
//                      [string delimter = "<br>\n"])
//
// splits a long string into two chunks (a start and an end chunk)
// of a given maximum length and seperates them by a given delimeter.
// a second chunk can be right-justified within maxlen.
// may be used to 'spread' a string over two lines.
//

function strtrmvistl($str, $maxlen = 64, $right_justify = false, $delimter = "<br>\n") {
    if(($len = strlen($str = chop($str))) > ($maxlen = max($maxlen, 12))) {
        $newstr = substr($str, 0, $maxlen - 3);

        if($len > ($maxlen - 3)) {
            $endlen = min(($len - strlen($newstr)), $maxlen - 3);
            $newstr .= "..." . $delimter;

            if($right_justify)
                $newstr .= str_pad('', $maxlen - $endlen - 3, ' ');

            $newstr .= "..." . substr($str, $len - $endlen);
        }

        return($newstr);
    }

    return($str);
}
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0
terry dot greenlaw at logicalshift dot com
9 years ago
Here's a simpler "simplest" way to toggle through a set of 1..n colors for web backgrounds:

<?php
$colours
= array('#000000', '#808080', '#A0A0A0', '#FFFFFF');

// Get a colour
$color = next($colors) or $color = reset($colors);
?>

The code doesn't need to know anything about the number of elements being cycled through. That way you won't have to tracking down all the code when changing the number of colors or the color values.
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-1
administrador(ensaimada)sphoera(punt)com
8 years ago
I've prepared this simple function to obtain a string delimited between tags (not only XML tags!). Anybody needs something like this?.

<?php

function get_string_between($string, $start, $end){
   
$string = " ".$string;
    
$ini = strpos($string,$start);
     if (
$ini == 0) return "";
    
$ini += strlen($start);    
    
$len = strpos($string,$end,$ini) - $ini;
     return
substr($string,$ini,$len);
}

$string = "this [custom] function is useless!!";
echo
get_string_between($string,"[","]");
// must return "custom";
?>
more functions at http://www.sphoera.com
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-1
Anonymous
8 years ago
to: james dot d dot baker at gmail dot com

PHP has a builtin function  for doing what your function does,

http://php.net/ucfirst
http://php.net/ucwords
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-1
mike &#34;eyes&#34; moe
7 years ago
Here is a truly random string generator it uses the most common string functions it will work on anywhere.

<?php
   
function random_string($max = 20){
       
$chars = explode(" ", "a b c d e f g h i j k l m n o p q r s t u v w x y z 0 1 2 3 4 5 6 7 8 9");
        for(
$i = 0; $i < $max; $i++){
           
$rnd = array_rand($chars);
           
$rtn .= base64_encode(md5($chars[$rnd]));
        }
        return
substr(str_shuffle(strtolower($rtn)), 0, $max);
    }
?>
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-1
SteveRusin
8 years ago
The functions below:

function beginsWith( $str, $sub )
function endsWith( $str, $sub )

Are correct, but flawed.  You'd need to use the === operator instead:

function beginsWith( $str, $sub ) {
   return ( substr( $str, 0, strlen( $sub ) ) === $sub );
}
function endsWith( $str, $sub ) {
   return ( substr( $str, strlen( $str ) - strlen( $sub ) ) === $sub );
}

Otherwise, endsWith would return "foobar.0" ends with ".0" as well as "0" or "00" or any amount of zeros because numerically .0 does equal 0.
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-1
rh at richardhoward dot net
9 years ago
<?php
/**
Utility class: static methods for cleaning & escaping untrusted (i.e.
user-supplied) strings.

Any string can (usually) be thought of as being in one of these 'modes':

pure = what the user actually typed / what you want to see on the page /
       what is actually stored in the DB
gpc  = incoming GET, POST or COOKIE data
sql  = escaped for passing safely to RDBMS via SQL (also, data from DB
       queries and file reads if you have magic_quotes_runtime on--which
       is rare)
html = safe for html display (htmlentities applied)

Always knowing what mode your string is in--using these methods to
convert between modes--will prevent SQL injection and cross-site scripting.

This class refers to its own namespace (so it can work in PHP 4--there is no
self keyword until PHP 5). Do not change the name of the class w/o changing
all the internal references.

Example usage: a POST value that you want to query with:
$username = Str::gpc2sql($_POST['username']);
*/

//This sets SQL escaping to use slashes; for Sybase(/MSSQL)-style escaping
// ( ' --> '' ), set to true.
define('STR_SYBASE', false);

class
Str {
    function
gpc2sql($gpc, $maxLength = false)
    {
        return
Str::pure2sql(Str::gpc2pure($gpc), $maxLength);
    }
    function
gpc2html($gpc, $maxLength = false)
    {
        return
Str::pure2html(Str::gpc2pure($gpc), $maxLength);
    }
    function
gpc2pure($gpc)
    {
        if (
ini_get('magic_quotes_sybase'))
           
$pure = str_replace("''", "'", $gpc);
        else
$pure = get_magic_quotes_gpc() ? stripslashes($gpc) : $gpc;
        return
$pure;
    }
    function
html2pure($html)
    {
        return
html_entity_decode($html);
    }
    function
html2sql($html, $maxLength = false)
    {
        return
Str::pure2sql(Str::html2pure($html), $maxLength);
    }
    function
pure2html($pure, $maxLength = false)
    {
        return
$maxLength ? htmlentities(substr($pure, 0, $maxLength))
                          :
htmlentities($pure);
    }
    function
pure2sql($pure, $maxLength = false)
    {
        if (
$maxLength) $pure = substr($pure, 0, $maxLength);
        return (
STR_SYBASE)
               ?
str_replace("'", "''", $pure)
               :
addslashes($pure);
    }
    function
sql2html($sql, $maxLength = false)
    {
       
$pure = Str::sql2pure($sql);
        if (
$maxLength) $pure = substr($pure, 0, $maxLength);
        return
Str::pure2html($pure);
    }
    function
sql2pure($sql)
    {
        return (
STR_SYBASE)
               ?
str_replace("''", "'", $sql)
               :
stripslashes($sql);
    }
}
?>
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-2
da (dot) blayde (a t) gmail (dot) com
8 years ago
Sometimes when converting integers to strings, it looks better to have the number spelled out. I wrote this function that converts integers from -999 to 999 into spelled out strings:

function int2str($int=0){
$doOnes=true;
$neg=$int<0?true:false;
$int=abs(round($int));
$str='';
switch(strlen($int)){
  case 1:$int='0'.$int;
  case 2:$int='0'.$int;
  case 3:$int.='';break;
  default:return $int;
}
switch($int{0}){
  case 1:$str.='one-hundred-';break;
  case 2:$str.='two-hundred-';break;
  case 3:$str.='three-hundred-';break;
  case 4:$str.='four-hundred-';break;
  case 5:$str.='five-hundred-';break;
  case 6:$str.='six-hundred-';break;
  case 7:$str.='seven-hundred-';break;
  case 8:$str.='eight-hundred-';break;
  case 9:$str.='nine-hundred-';break;
}
switch($int{1}){
  case 1:
   switch($int{2}){
    case 0:$str.='ten-';break;
    case 1:$str.='eleven-';break;
    case 2:$str.='twelve-';break;
    case 3:$str.='thirteen-';break;
    case 4:$str.='fourteen-';break;
    case 5:$str.='fifteen-';break;
    case 6:$str.='sixteen-';break;
    case 7:$str.='seventeen-';break;
    case 8:$str.='eighteen-';break;
    case 9:$str.='nineteen-';break;
   }
   $doOnes=false;
  break;
  case 2:$str.='twenty-';break;
  case 3:$str.='thirty-';break;
  case 4:$str.='forty-';break;
  case 5:$str.='fifty-';break;
  case 6:$str.='sixty-';break;
  case 7:$str.='seventy-';break;
  case 8:$str.='eighty-';break;
  case 9:$str.='ninety-';break;
}
if($doOnes){
  switch($int{2}){
   case 1:$str.='one-';break;
   case 2:$str.='two-';break;
   case 3:$str.='three-';break;
   case 4:$str.='four-';break;
   case 5:$str.='five-';break;
   case 6:$str.='six-';break;
   case 7:$str.='seven-';break;
   case 8:$str.='eight-';break;
   case 9:$str.='nine-';break;
}}
$str=substr($str,0,-1);
if($neg){
  $str='negative '.$str;
}
if($int=='000'){
  $str='zero';
}
return $str;
}

Hope this helps someone,
-Blayde
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-1
Stephen Dewey
5 years ago
If you want a function to return all text in a string up to the Nth occurrence of a substring, try the below function.

Works in PHP >= 5.

(Pommef provided another sample function for this purpose below, but I believe it is incorrect.)

<?php

// Returns all of $haystack up to (but excluding) the $n_occurrence occurrence of $needle. Therefore:
//        If there are < $n_occurrence occurrences of $needle in $haystack, the entire string will be returned.
//        If there are >= $n_occurrence occurrences of $needle in $haystack, the returned string will end before the $n_occurrence'th needle.
// This function only makes sense for $n_occurrence >= 1
function nsubstr($needle, $haystack, $n_occurrence)
{
   
// After exploding by $needle, every entry in $arr except (possibly) part of the last entry should have its content returned.
   
$arr = explode($needle,$haystack,$n_occurrence);
   
// Examine last entry in $arr. If it contains $needle, cut out all text except for the text before $needle.
   
$last = count($arr) - 1;
   
$pos_in_last = strpos($arr[$last],$needle);
   
    if (
$pos_in_last !== false)
       
$arr[$last] = substr($arr[$last],0,$pos_in_last);
   
    return
implode($needle,$arr);
}

$string = 'd24jkdslgjldk2424jgklsjg24jskgldjk24';

print
'S:  ' . $string . '<br>';
print
'1: ' . nsubstr('24',$string,1) . '<br>';
print
'2: ' . nsubstr('24',$string,2) . '<br>';
print
'3: ' . nsubstr('24',$string,3) . '<br>';
print
'4: ' . nsubstr('24',$string,4) . '<br>';
print
'5: ' . nsubstr('24',$string,5) . '<br>';
print
'6: ' . nsubstr('24',$string,6) . '<br>';
print
'7: ' . nsubstr('24',$string,7) . '<br>';

/*
// prints:
S: d24jkdslgjldk2424jgklsjg24jskgldjk24
1: d
2: d24jkdslgjldk
3: d24jkdslgjldk24
4: d24jkdslgjldk2424jgklsjg
5: d24jkdslgjldk2424jgklsjg24jskgldjk
6: d24jkdslgjldk2424jgklsjg24jskgldjk24
7: d24jkdslgjldk2424jgklsjg24jskgldjk24
*/

?>

Note that this function can be combined with wordwrap() to accomplish a routine but fairly difficult web design goal, namely, limiting inline HTML text to a certain number of lines. wordwrap() can break your string using <br>, and then you can use this function to only return text up to the N'th <br>.

You will still have to make a conservative guess of the max number of characters per line with wordwrap(), but you can be more precise than if you were simply truncating a multiple-line string with substr().

See example:

<?php

$text
= 'Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Pellentesque id massa. Duis sollicitudin ipsum vel diam. Aliquam pulvinar sagittis felis. Nullam hendrerit semper elit. Donec convallis mollis risus. Cras blandit mollis turpis. Vivamus facilisis, sapien at tincidunt accumsan, arcu dolor suscipit sem, tristique convallis ante ante id diam. Curabitur mollis, lacus vel gravida accumsan, enim quam condimentum est, vitae rutrum neque magna ac enim.';

$wrapped_text = wordwrap($text,100,'<br>',true);

$three_lines = nsubstr('<br>',$wrapped_text,3);

print
'<br><br>' . $three_lines;

$four_lines = nsubstr('<br>',$wrapped_text,4);

print
'<br><br>' . $four_lines;

/*
prints:

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Pellentesque id massa. Duis sollicitudin
ipsum vel diam. Aliquam pulvinar sagittis felis. Nullam hendrerit semper elit. Donec convallis
mollis risus. Cras blandit mollis turpis. Vivamus facilisis, sapien at tincidunt accumsan, arcu

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Pellentesque id massa. Duis sollicitudin
ipsum vel diam. Aliquam pulvinar sagittis felis. Nullam hendrerit semper elit. Donec convallis
mollis risus. Cras blandit mollis turpis. Vivamus facilisis, sapien at tincidunt accumsan, arcu
dolor suscipit sem, tristique convallis ante ante id diam. Curabitur mollis, lacus vel gravida

*/

?>
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-1
Verdauga
6 years ago
Just a note in regards to bloopletech a few posts down:

The word "and" should not be used when converting numbers to text.  "And" (at least in US English) should only be used to indicate the decimal place.

Example:
1,796,706 => one million, seven hundred ninety-six thousand, seven hundred six.
594,359.34 => five hundred ninety four thousand, three hundred fifty nine and thirty four hundredths
up
-1
php at moechofe dot com
9 years ago
<?php
 
/*
  * str_match
  *
  * return a string with only cacacteres defined in a expression return false if the expression is not valid
  *
  * @param $str string the string
  * @param $match the expression based on the class definition off a PCRE regular expression.
  *   the '[', ']', '\' and '^' at class start need to be escaped.
  *   like : -a-z0-9_@.
  */
 
function str_match( $str, $match )
  {
   
$return = '';
    if(
eregi( '(.*)', $match, $class ) )
    {
     
$match = '['.$regs[1].']';
      for(
$i=0; $i<strlen($str); $i++ )
      if(
ereg( '['.$class[1].']', $str[$i] ) )
     
$return .= $str{$i};
      return
$return;
    }
    else return
false;
  }

 
/*
  * example
  * accept only alphanum caracteres from the GET/POST parameters 'a'
  */

 
if( ! empty($_REQUEST['a']) )
   
$_REQUEST['a'] = str_match( $_REQUEST['a'], 'a-zA-Z0-9' );
  else
   
$_REQUEST['a'] = 'default';
?>
up
-1
m
6 years ago
Regarding the code for the function beginsWith($str, $sub), I found that it has problems when only one character is present after the string searched for. I found that this works better instead:

<?php
function beginsWith($str, $sub) {
    return (
strncmp($str, $sub, strlen($sub)) == 0);
}
?>
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-1
Pommef
9 years ago
Example: Give me everything up to the fourth occurance of '/'.

<?php

   $haystack
= "/home/username/www/index.php";
  
$needle = "/";
 
   function
strnpos($haystack, $needle, $occurance, $pos = 0) {
       
       
$res = implode($needle,$haystack);
       
       
$res = array_slice($res, $pos$occurance);
       
        return
explode ($needle,$res);
    }
?>
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-3
Tomek Rychtyk
2 years ago
Get the intersection of two strings using array_intersect

<?php

function string_intersect($string1, $string2)
{
   
$array1 = $array2 = array();

    for(
$i = 0, $j = 0, $s1_len = strlen($string1), $s2_len = strlen($string2);($i < $s1_len) || ($j < $s2_len); $i++, $j++) {
        if(
$i < $s1_len) {
           
$array1[] = $string1[$i];
        }
        if(
$j < $s2_len) {
           
$array2[] = $string2[$j];
        }
    }

    return
implode('', array_intersect($array1, $array2));
}

?>

For more advanced comparison you can use array_uintersect as well.
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-2
admin at rotarymulundeast dot org
7 years ago
Here's an easier way to find nth...

function nth($numbex){
  if ($numbex%10 == 1 && $numbex%100 != 11) $sth='st';
  elseif ($numbex%10 == 2 && $numbex%100 != 12) $sth='nd';
  elseif ($numbex%10 == 3 && $numbex%100 != 13) $sth='rd';
  else $sth = 'th';
  return $sth;
}

there is is no need to check if the user has entered a non-integer as we may be using this function for expressing variables as well eg. ith value of x , nth root of z ,etc...
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