String Functions

See Also

For even more powerful string handling and manipulating functions take a look at the POSIX regular expression functions and the Perl compatible regular expression functions.

Table of Contents

  • addcslashes — Quote string with slashes in a C style
  • addslashes — Quote string with slashes
  • bin2hex — Convert binary data into hexadecimal representation
  • chop — Alias of rtrim
  • chr — Return a specific character
  • chunk_split — Split a string into smaller chunks
  • convert_cyr_string — Convert from one Cyrillic character set to another
  • convert_uudecode — Decode a uuencoded string
  • convert_uuencode — Uuencode a string
  • count_chars — Return information about characters used in a string
  • crc32 — Calculates the crc32 polynomial of a string
  • crypt — One-way string hashing
  • echo — Output one or more strings
  • explode — Split a string by string
  • fprintf — Write a formatted string to a stream
  • get_html_translation_table — Returns the translation table used by htmlspecialchars and htmlentities
  • hebrev — Convert logical Hebrew text to visual text
  • hebrevc — Convert logical Hebrew text to visual text with newline conversion
  • hex2bin — Decodes a hexadecimally encoded binary string
  • html_entity_decode — Convert all HTML entities to their applicable characters
  • htmlentities — Convert all applicable characters to HTML entities
  • htmlspecialchars_decode — Convert special HTML entities back to characters
  • htmlspecialchars — Convert special characters to HTML entities
  • implode — Join array elements with a string
  • join — Alias of implode
  • lcfirst — Make a string's first character lowercase
  • levenshtein — Calculate Levenshtein distance between two strings
  • localeconv — Get numeric formatting information
  • ltrim — Strip whitespace (or other characters) from the beginning of a string
  • md5_file — Calculates the md5 hash of a given file
  • md5 — Calculate the md5 hash of a string
  • metaphone — Calculate the metaphone key of a string
  • money_format — Formats a number as a currency string
  • nl_langinfo — Query language and locale information
  • nl2br — Inserts HTML line breaks before all newlines in a string
  • number_format — Format a number with grouped thousands
  • ord — Return ASCII value of character
  • parse_str — Parses the string into variables
  • print — Output a string
  • printf — Output a formatted string
  • quoted_printable_decode — Convert a quoted-printable string to an 8 bit string
  • quoted_printable_encode — Convert a 8 bit string to a quoted-printable string
  • quotemeta — Quote meta characters
  • rtrim — Strip whitespace (or other characters) from the end of a string
  • setlocale — Set locale information
  • sha1_file — Calculate the sha1 hash of a file
  • sha1 — Calculate the sha1 hash of a string
  • similar_text — Calculate the similarity between two strings
  • soundex — Calculate the soundex key of a string
  • sprintf — Return a formatted string
  • sscanf — Parses input from a string according to a format
  • str_getcsv — Parse a CSV string into an array
  • str_ireplace — Case-insensitive version of str_replace.
  • str_pad — Pad a string to a certain length with another string
  • str_repeat — Repeat a string
  • str_replace — Replace all occurrences of the search string with the replacement string
  • str_rot13 — Perform the rot13 transform on a string
  • str_shuffle — Randomly shuffles a string
  • str_split — Convert a string to an array
  • str_word_count — Return information about words used in a string
  • strcasecmp — Binary safe case-insensitive string comparison
  • strchr — Alias of strstr
  • strcmp — Binary safe string comparison
  • strcoll — Locale based string comparison
  • strcspn — Find length of initial segment not matching mask
  • strip_tags — Strip HTML and PHP tags from a string
  • stripcslashes — Un-quote string quoted with addcslashes
  • stripos — Find the position of the first occurrence of a case-insensitive substring in a string
  • stripslashes — Un-quotes a quoted string
  • stristr — Case-insensitive strstr
  • strlen — Get string length
  • strnatcasecmp — Case insensitive string comparisons using a "natural order" algorithm
  • strnatcmp — String comparisons using a "natural order" algorithm
  • strncasecmp — Binary safe case-insensitive string comparison of the first n characters
  • strncmp — Binary safe string comparison of the first n characters
  • strpbrk — Search a string for any of a set of characters
  • strpos — Find the position of the first occurrence of a substring in a string
  • strrchr — Find the last occurrence of a character in a string
  • strrev — Reverse a string
  • strripos — Find the position of the last occurrence of a case-insensitive substring in a string
  • strrpos — Find the position of the last occurrence of a substring in a string
  • strspn — Finds the length of the initial segment of a string consisting entirely of characters contained within a given mask.
  • strstr — Find the first occurrence of a string
  • strtok — Tokenize string
  • strtolower — Make a string lowercase
  • strtoupper — Make a string uppercase
  • strtr — Translate characters or replace substrings
  • substr_compare — Binary safe comparison of two strings from an offset, up to length characters
  • substr_count — Count the number of substring occurrences
  • substr_replace — Replace text within a portion of a string
  • substr — Return part of a string
  • trim — Strip whitespace (or other characters) from the beginning and end of a string
  • ucfirst — Make a string's first character uppercase
  • ucwords — Uppercase the first character of each word in a string
  • vfprintf — Write a formatted string to a stream
  • vprintf — Output a formatted string
  • vsprintf — Return a formatted string
  • wordwrap — Wraps a string to a given number of characters

Коментарии

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 "/";
   
   
$root_dir substr($haystack0strnpos($haystack$needle4));
   
    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!
2005-01-02 10:32:44
http://php5.kiev.ua/manual/ru/ref.strings.html
I'm converting 30 year old code and needed a string TAB function:

  //tab function similar to TAB used in old BASIC languages
  //though some of them did not truncate if the string were
  //longer than the requested position
  function tab($instring="",$topos=0){
    if(strlen($instring)<$topos){
      $result=str_pad($instring,$topos-1," ",STR_PAD_RIGHT);
    }else{
      $result=substr($instring,0,$topos-1);
    }
    return $result;
  }

  $pline="String with this tab to 50 and";
  $tline=tab($pline,50)."finish it.";
  echo $tline.PHP_EOL;
  $pline="101010101020202020203030303030404040404050505050506060606060";
  $tline=tab($pline,50)."finish it.";
  echo $tline.PHP_EOL;

  //Results in this output:
  //String with this tab to 50 and                   finish it.
  //1010101010202020202030303030304040404040505050505finish it.
2021-08-25 20:44:03
http://php5.kiev.ua/manual/ru/ref.strings.html

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