(PHP 3 <= 3.0.18, PHP 4 >= 4.0.0)
substr -- Return part of a string
Description
string substr (string string, int start [, int length])
Substr returns the portion of string specified by the
start and length parameters.
If start is positive, 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.
|
Example 1. Basic substr() usage
$rest = substr("abcdef", 1); // returns "bcdef"
$rest = substr("abcdef", 1, 3); // returns "bcd"
$rest = substr("abcdef", 0, 4); // returns "abcd"
$rest = substr("abcdef", 0, 8); // returns "abcdef"
|
|
If start is negative, the returned string will start at the
start'th character from the end of string.
|
Example 2. Using a negative start
$rest = substr("abcdef", -1); // returns "f"
$rest = substr("abcdef", -2); // returns "ef"
$rest = substr("abcdef", -3, 1); // returns "d"
|
|
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 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 3. Using a negative length
$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"
|
|
See also strrchr() and ereg().
|
