substr (PHP 3, PHP 4, PHP 5) substr -- Return part of a string Descriptionstring substr ( string string, int start [, int length] )
Returns the portion of string specified by the
start and length parameters.
Parameters
string
The input string.
start
If start is non-negative, the returned string
will start at the start'th position in
string, counting from zero. For instance,
in the string 'abcdef', the character at
position 0 is 'a', the
character at position 2 is
'c', and so forth.
If start is negative, the returned string
will start at the start'th character
from the end of string.
Example 1. Using a negative start
<?php
$rest = substr("abcdef", -1); // returns "f"
$rest = substr("abcdef", -2); // returns "ef"
$rest = substr("abcdef", -3, 1); // returns "d"
?>
|
|
length
If length is given and is positive, the string
returned will contain at most length characters
beginning from start (depending on the length of
string). If string is less
than or equal to start characters long, FALSE
will be returned.
If length is given and is negative, then that many
characters will be omitted from the end of string
(after the start position has been calculated when a
start is negative). If
start denotes a position beyond this truncation,
an empty string will be returned.
Example 2. Using a negative length
<?php
$rest = substr("abcdef", 0, -1); // returns "abcde"
$rest = substr("abcdef", 2, -1); // returns "cde"
$rest = substr("abcdef", 4, -4); // returns ""
$rest = substr("abcdef", -3, -1); // returns "de"
?>
|
|
Return Values
Returns the extracted part of string.
Examples
Example 3. Basic substr() usage
<?php
echo substr('abcdef', 1); // bcdef
echo substr('abcdef', 1, 3); // bcd
echo substr('abcdef', 0, 4); // abcd
echo substr('abcdef', 0, 8); // abcdef
echo substr('abcdef', -1, 1); // f
// Accessing single characters in a string
// can also be achived using "curly braces"
$string = 'abcdef';
echo $string{0}; // a
echo $string{3}; // d
echo $string{strlen($string)-1}; // f
?>
|
|
|
|
