PHP: String Functions - Manual (original) (raw)

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 — Generate a single-byte string from a number
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 a 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 HTML entities to their corresponding characters
htmlentities — Convert all applicable characters to HTML entities
htmlspecialchars — Convert special characters to HTML entities
htmlspecialchars_decode — Convert special HTML entities back to characters
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 — Calculate the md5 hash of a string
md5_file — Calculates the md5 hash of a given file
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 — Convert the first byte of a string to a value between 0 and 255
parse_str — Parse a string as a URL query string
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 — Calculate the sha1 hash of a string
sha1_file — Calculate the sha1 hash of a file
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_contains — Determine if a string contains a given substring
str_decrement — Decrement an alphanumeric string
str_ends_with — Checks if a string ends with a given substring
str_getcsv — Parse a CSV string into an array
str_increment — Increment an alphanumeric string
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_starts_with — Checks if a string starts with a given substring
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 — Return part of a string
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
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
utf8_decode — Converts a string from UTF-8 to ISO-8859-1, replacing invalid or unrepresentable characters
utf8_encode — Converts a string from ISO-8859-1 to UTF-8
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

Found A Problem?

lrirwin at alum dot wustl dot edu ¶

4 years ago

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){
      <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>r</mi><mi>e</mi><mi>s</mi><mi>u</mi><mi>l</mi><mi>t</mi><mo>=</mo><mi>s</mi><mi>t</mi><msub><mi>r</mi><mi>p</mi></msub><mi>a</mi><mi>d</mi><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">result=str_pad(</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6944em;"></span><span class="mord mathnormal">res</span><span class="mord mathnormal">u</span><span class="mord mathnormal">lt</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1.0361em;vertical-align:-0.2861em;"></span><span class="mord mathnormal">s</span><span class="mord mathnormal">t</span><span class="mord"><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.1514em;"><span style="top:-2.55em;margin-left:-0.0278em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">p</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.2861em;"><span></span></span></span></span></span></span><span class="mord mathnormal">a</span><span class="mord mathnormal">d</span><span class="mopen">(</span></span></span></span>instring,$topos-1," ",STR_PAD_RIGHT);
    }else{
      <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>r</mi><mi>e</mi><mi>s</mi><mi>u</mi><mi>l</mi><mi>t</mi><mo>=</mo><mi>s</mi><mi>u</mi><mi>b</mi><mi>s</mi><mi>t</mi><mi>r</mi><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">result=substr(</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6944em;"></span><span class="mord mathnormal">res</span><span class="mord mathnormal">u</span><span class="mord mathnormal">lt</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">s</span><span class="mord mathnormal">u</span><span class="mord mathnormal">b</span><span class="mord mathnormal">s</span><span class="mord mathnormal">t</span><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="mopen">(</span></span></span></span>instring,0,$topos-1);
    }
    return $result;
  }

  $pline="String with this tab to 50 and";
  <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>t</mi><mi>l</mi><mi>i</mi><mi>n</mi><mi>e</mi><mo>=</mo><mi>t</mi><mi>a</mi><mi>b</mi><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">tline=tab(</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6944em;"></span><span class="mord mathnormal" style="margin-right:0.01968em;">tl</span><span class="mord mathnormal">in</span><span class="mord mathnormal">e</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">t</span><span class="mord mathnormal">ab</span><span class="mopen">(</span></span></span></span>pline,50)."finish it.";
  echo $tline.PHP_EOL;
  $pline="101010101020202020203030303030404040404050505050506060606060";
  <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>t</mi><mi>l</mi><mi>i</mi><mi>n</mi><mi>e</mi><mo>=</mo><mi>t</mi><mi>a</mi><mi>b</mi><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">tline=tab(</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6944em;"></span><span class="mord mathnormal" style="margin-right:0.01968em;">tl</span><span class="mord mathnormal">in</span><span class="mord mathnormal">e</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">t</span><span class="mord mathnormal">ab</span><span class="mopen">(</span></span></span></span>pline,50)."finish it.";
  echo $tline.PHP_EOL;

  //Results in this output:
  //String with this tab to 50 and                   finish it.
  //1010101010202020202030303030304040404040505050505finish it.

kristin at greenapple dot on dot ca ¶

20 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, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>n</mi><mi>e</mi><mi>e</mi><mi>d</mi><mi>l</mi><mi>e</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">needle, </annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mord mathnormal">ee</span><span class="mord mathnormal">d</span><span class="mord mathnormal" style="margin-right:0.01968em;">l</span><span class="mord mathnormal">e</span><span class="mpunct">,</span></span></span></span>occurance, $pos = 0) {
        
        for ($i = 1; <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>i</mi><mo>&lt;</mo><mo>=</mo></mrow><annotation encoding="application/x-tex">i &lt;= </annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.6986em;vertical-align:-0.0391em;"></span><span class="mord mathnormal">i</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">&lt;=</span></span></span></span>occurance; $i++) {
            <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>p</mi><mi>o</mi><mi>s</mi><mo>=</mo><mi>s</mi><mi>t</mi><mi>r</mi><mi>p</mi><mi>o</mi><mi>s</mi><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">pos = strpos(</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.625em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">p</span><span class="mord mathnormal">os</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">s</span><span class="mord mathnormal">t</span><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="mord mathnormal">p</span><span class="mord mathnormal">os</span><span class="mopen">(</span></span></span></span>haystack, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>n</mi><mi>e</mi><mi>e</mi><mi>d</mi><mi>l</mi><mi>e</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">needle, </annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">n</span><span class="mord mathnormal">ee</span><span class="mord mathnormal">d</span><span class="mord mathnormal" style="margin-right:0.01968em;">l</span><span class="mord mathnormal">e</span><span class="mpunct">,</span></span></span></span>pos) + 1;
        }
        return $pos - 1;
        
    }

?>

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

<?php

    $haystack = "/home/username/www/index.php";
    $needle = "/";
    
    <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>r</mi><mi>o</mi><mi>o</mi><msub><mi>t</mi><mi>d</mi></msub><mi>i</mi><mi>r</mi><mo>=</mo><mi>s</mi><mi>u</mi><mi>b</mi><mi>s</mi><mi>t</mi><mi>r</mi><mo stretchy="false">(</mo></mrow><annotation encoding="application/x-tex">root_dir = substr(</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8095em;vertical-align:-0.15em;"></span><span class="mord mathnormal">roo</span><span class="mord"><span class="mord mathnormal">t</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3361em;"><span style="top:-2.55em;margin-left:0em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">d</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord mathnormal">i</span><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">s</span><span class="mord mathnormal">u</span><span class="mord mathnormal">b</span><span class="mord mathnormal">s</span><span class="mord mathnormal">t</span><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="mopen">(</span></span></span></span>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!

PHP: String Functions - Manual (original) (raw)

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