trim(3) [php man page]
TRIM(3) 1 TRIM(3) trim - Strip whitespace (or other characters) from the beginning and end of a string SYNOPSIS
string trim (string $str, [string $character_mask = " 0r B"]) DESCRIPTION
This function returns a string with whitespace stripped from the beginning and end of $str. Without the second parameter, trim(3) will strip these characters: o " " (ASCII 32 ( 0x20)), an ordinary space. o " " (ASCII 9 ( 0x09)), a tab. o " " (ASCII 10 ( 0x0A)), a new line (line feed). o " " (ASCII 13 ( 0x0D)), a carriage return. o " " (ASCII 0 ( 0x00)), the NUL-byte. o "x0B" (ASCII 11 ( 0x0B)), a vertical tab. PARAMETERS
o $str - The string that will be trimmed. o $character_mask - Optionally, the stripped characters can also be specified using the $character_mask parameter. Simply list all characters that you want to be stripped. With .. you can specify a range of characters. RETURN VALUES
The trimmed string. EXAMPLES
Example #1 Usage example of trim(3) <?php $text = " These are a few words :) ... "; $binary = "x09Example stringx0A"; $hello = "Hello World"; var_dump($text, $binary, $hello); print " "; $trimmed = trim($text); var_dump($trimmed); $trimmed = trim($text, " ."); var_dump($trimmed); $trimmed = trim($hello, "Hdle"); var_dump($trimmed); $trimmed = trim($hello, 'HdWr'); var_dump($trimmed); // trim the ASCII control characters at the beginning and end of $binary // (from 0 to 31 inclusive) $clean = trim($binary, "x00..x1F"); var_dump($clean); ?> The above example will output: string(32) " These are a few words :) ... " string(16) " Example string " string(11) "Hello World" string(28) "These are a few words :) ..." string(24) "These are a few words :)" string(5) "o Wor" string(9) "ello Worl" string(14) "Example string" Example #2 Trimming array values with trim(3) <?php function trim_value(&$value) { $value = trim($value); } $fruit = array('apple','banana ', ' cranberry '); var_dump($fruit); array_walk($fruit, 'trim_value'); var_dump($fruit); ?> The above example will output: array(3) { [0]=> string(5) "apple" [1]=> string(7) "banana " [2]=> string(11) " cranberry " } array(3) { [0]=> string(5) "apple" [1]=> string(6) "banana" [2]=> string(9) "cranberry" } NOTES
Note Possible gotcha: removing middle characters Because trim(3) trims characters from the beginning and end of a string, it may be confusing when characters are (or are not) removed from the middle. trim('abc', 'bad') removes both 'a' and 'b' because it trims 'a' thus moving 'b' to the beginning to also be trimmed. So, this is why it "works" whereas trim('abc', 'b') seemingly does not. SEE ALSO
ltrim(3), rtrim(3), str_replace(3). PHP Documentation Group TRIM(3)
Check Out this Related Man Page
textutil::trim(n) Text and string utilities, macro processing textutil::trim(n) __________________________________________________________________________________________________________________________________________________ NAME
textutil::trim - Procedures to trim strings SYNOPSIS
package require Tcl 8.2 package require textutil::trim ?0.7? ::textutil::trim::trim string ?regexp? ::textutil::trim::trimleft string ?regexp? ::textutil::trim::trimright string ?regexp? ::textutil::trim::trimPrefix string prefix ::textutil::trim::trimEmptyHeading string _________________________________________________________________ DESCRIPTION
The package textutil::trim provides commands that trim strings using arbitrary regular expressions. The complete set of procedures is described below. ::textutil::trim::trim string ?regexp? Remove in string any leading and trailing substring according to the regular expression regexp and return the result as a new string. This is done for all lines in the string, that is any substring between 2 newline chars, or between the beginning of the string and a newline, or between a newline and the end of the string, or, if the string contain no newline, between the beginning and the end of the string. The regular expression regexp defaults to "[ \t]+". ::textutil::trim::trimleft string ?regexp? Remove in string any leading substring according to the regular expression regexp and return the result as a new string. This apply on any line in the string, that is any substring between 2 newline chars, or between the beginning of the string and a newline, or between a newline and the end of the string, or, if the string contain no newline, between the beginning and the end of the string. The regular expression regexp defaults to "[ \t]+". ::textutil::trim::trimright string ?regexp? Remove in string any trailing substring according to the regular expression regexp and return the result as a new string. This apply on any line in the string, that is any substring between 2 newline chars, or between the beginning of the string and a newline, or between a newline and the end of the string, or, if the string contain no newline, between the beginning and the end of the string. The regular expression regexp defaults to "[ \t]+". ::textutil::trim::trimPrefix string prefix Removes the prefix from the beginning of string and returns the result. The string is left unchanged if it doesn't have prefix at its beginning. ::textutil::trim::trimEmptyHeading string Looks for empty lines (including lines consisting of only whitespace) at the beginning of the string and removes it. The modified string is returned as the result of the command. BUGS, IDEAS, FEEDBACK This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category textutil of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may have for either package and/or documentation. SEE ALSO
regexp(n), split(n), string(n) KEYWORDS
prefix, regular expression, string, trimming CATEGORY
Text processing textutil 0.7 textutil::trim(n)