echo
I'm sure you guys get just a bit frustrated at times when you need a fraction of a very simple string and you use "explode()", but then you have to define a whole extra variable. (That is because you need to store a function-returned array in a variable before you can extract a value).
If you're extracting the last half, or third, of a string, there's an easy inline workaround. Check this:
<?php
$mystr = "separated-text";
print(str_replace("-","",strstr("-",$mystr)));
//Returns "text"
?>
If the separator (dash) can be left in, you don't even need the "str_replace()" function.
Lets try this with 3 fractions:
<?php
$mystr = "separated-text-again";
//Comment submission wouldn't let me
// combine this into one statement.
// That's okay, it's more readable.
$split1 = str_replace("-","",strstr("-",$mystr));
print(str_replace("-","",strstr("-",$split1)));
//Returns "again"
?>
Anything more than 3 fractions gets really confusing, in that case you should use "explode()".
Hope this helps!
~Cody G.
explode
(PHP 4, PHP 5)
explode — Split a string by string
Description
array explode
( string $delimiter
, string $string
[, int $limit
] )
Returns an array of strings, each of which is a substring of string formed by splitting it on boundaries formed by the string delimiter.
Parameters
- delimiter
-
The boundary string.
- string
-
The input string.
- limit
-
If limit is set and positive, the returned array will contain a maximum of limit elements with the last element containing the rest of string.
If the limit parameter is negative, all components except the last -limit are returned.
If the limit parameter is zero, then this is treated as 1.
Although implode() can, for historical reasons, accept its parameters in either order, explode() cannot. You must ensure that the delimiter argument comes before the string argument.
Return Values
Returns an array of strings created by splitting the string parameter on boundaries formed by the delimiter.
If delimiter is an empty string (""), explode() will return FALSE. If delimiter contains a value that is not contained in string and a negative limit is used, then an empty arraywill be returned, otherwise an array containing string will be returned.
Changelog
| Version | Description |
|---|---|
| 5.1.0 | Support for negative limits was added |
| 4.0.1 | The limit parameter was added |
Examples
Example #1 explode() examples
<?php
// Example 1
$pizza = "piece1 piece2 piece3 piece4 piece5 piece6";
$pieces = explode(" ", $pizza);
echo $pieces[0]; // piece1
echo $pieces[1]; // piece2
// Example 2
$data = "foo:*:1023:1000::/home/foo:/bin/sh";
list($user, $pass, $uid, $gid, $gecos, $home, $shell) = explode(":", $data);
echo $user; // foo
echo $pass; // *
?>
Example #2 limit parameter examples
<?php
$str = 'one|two|three|four';
// positive limit
print_r(explode('|', $str, 2));
// negative limit (since PHP 5.1)
print_r(explode('|', $str, -1));
?>
The above example will output:
Array
(
[0] => one
[1] => two|three|four
)
Array
(
[0] => one
[1] => two
[2] => three
)
Notes
Note: This function is binary-safe.
See Also
- preg_split() - Split string by a regular expression
- str_split() - Convert a string to an array
- str_word_count() - Return information about words used in a string
- strtok() - Tokenize string
- implode() - Join array elements with a string
add a note
User Contributed Notesexplode
Cody G.
08-Aug-2010 03:41
08-Aug-2010 03:41
m0gr14 at gmail dot com
31-Jul-2010 04:02
31-Jul-2010 04:02
Here's a function for "multi" exploding a string.
<?php
//the function
//Param 1 has to be an Array
//Param 2 has to be a String
function multiexplode ($delimiters,$string) {
$ary = explode($delimiters[0],$string);
array_shift($delimiters);
if($delimiters != NULL) {
foreach($ary as $key => $val) {
$ary[$key] = multiexplode($delimiters, $val);
}
}
return $ary;
}
// Example of use
$string = "1-2-3|4-5|6:7-8-9-0|1,2:3-4|5";
$delimiters = Array(",",":","|","-");
$res = multiexplode($delimiters,$string);
echo '<pre>';
print_r($res);
echo '</pre>';
//returns
/*
Array
(
[0] => Array
(
[0] => Array
(
[0] => Array
(
[0] => 1
[1] => 2
[2] => 3
)
[1] => Array
(
[0] => 4
[1] => 5
)
[2] => Array
(
[0] => 6
)
)
[1] => Array
(
[0] => Array
(
[0] => 7
[1] => 8
[2] => 9
[3] => 0
)
[1] => Array
(
[0] => 1
)
)
)
[1] => Array
(
[0] => Array
(
[0] => Array
(
[0] => 2
)
)
[1] => Array
(
[0] => Array
(
[0] => 3
[1] => 4
)
[1] => Array
(
[0] => 5
)
)
)
)
*/
?>
info at noextratime dot com
04-Jul-2010 10:09
04-Jul-2010 10:09
Here is a function for "double" exploding a string, like in the case of a flattened multi-dimensional array.
<?php
function doubleExplode ($del1, $del2, $array){
$array1 = explode("$del1", $array);
foreach($array1 as $key=>$value){
$array2 = explode("$del2", $value);
foreach($array2 as $key2=>$value2){
$array3[] = $value2;
}
}
$afinal = array();
for ( $i = 0; $i <= count($array3); $i += 2) {
if($array3[$i]!=""){
$afinal[trim($array3[$i])] = trim($array3[$i+1]);
}
}
return $afinal;
}
$proddetails = 'Size=Large, Color=Black';
$test = doubleExplode(',', '=', $proddetails);
print_r($test);
?>
/*
Array
(
[Size] => Large
[Color] => Black
)
*/
jessebusman at gmail dot com
27-May-2010 09:45
27-May-2010 09:45
Sometimes you need to explode a string by different delimiters. In that case you can use this function:
<?php
print_r(explodeX(Array(".","!"," ","?",";"),"This.sentence?contains wrong;characters"));
// Returns:
// Array("This","sentence","contains","wrong","characters")
function explodeX($delimiters,$string)
{
$return_array = Array($string); // The array to return
$d_count = 0;
while (isset($delimiters[$d_count])) // Loop to loop through all delimiters
{
$new_return_array = Array();
foreach($return_array as $el_to_split) // Explode all returned elements by the next delimiter
{
$put_in_new_return_array = explode($delimiters[$d_count],$el_to_split);
foreach($put_in_new_return_array as $substr) // Put all the exploded elements in array to return
{
$new_return_array[] = $substr;
}
}
$return_array = $new_return_array; // Replace the previous return array by the next version
$d_count++;
}
return $return_array; // Return the exploded elements
}
?>
Onur Nizam onur dot nizam at yahoo dot com
16-May-2010 09:27
16-May-2010 09:27
The regular expression parameters such as \n or \t can be used as well as other strings as the delimeter which can be used to parse any given text files or downloaded web pages to read line by line.
An example may be considered as, name surname and phone numbers are written into a text file line by line and columns are seperated by tabs, can be exploded and read easily through the return and tab characters. After storing them in the array they can be manipulated or displayed in any other formats.
<?php
// Explode text file and store each row of the file into the array elements
function explodeRows($data) {
$rowsArr = explode("\n", $data);
return $rowsArr;
}
// Explode the columns according to tabs
function explodeTabs($singleLine) {
$tabsArr = explode("\t", $singleLine);
return $tabsArr;
}
// Open the text file and get the content
$filename = "phonebook.txt";
$handle = fopen($filename, 'r');
$data = fread($handle, filesize($filename));
$rowsArr = explodeRows($data);
// Display content which is exploded by regular expression parameters \n and \t
for($i=0;$i<count($rowsArr);$i++) {
$lineDetails = explodeTabs($rowsArr[$i]);
echo "<br>Name : " . $lineDetails[0];
echo "<br>Surname : " . $lineDetails[1];
echo "<br>Tel Number : " . $lineDetails[2];
echo "<br><br>";
}
/*
phonebook.txt text file can be something like this;
name1 sname1 +905429998877
name2 sname2 +905429998876
name3 sname3 +905429998875
The output will be as follows;
Name : name1
Surname : sname1
Tel Number : +905429998877
Name : name2
Surname : sname2
Tel Number : +905429998876
Name : name3
Surname : sname3
Tel Number : +905429998875
*/
?>
drieick at hotmail dot com
22-Apr-2010 05:34
22-Apr-2010 05:34
When explode is given an empty $string, it'll return an array with a single empty element.
<?php
# returns Array([0] => );
print_r(explode(',', ''));
?>
This is not a bug, but it can be pretty tricky (especially with callbacks that expect a certain type of array). So, be sure to check your arrays. It's not a bug, because there's nothing to split.
locoluis at gmail dot com
08-Apr-2010 06:02
08-Apr-2010 06:02
That with all stateful encodings that use bytes between 0x00 and 0x7f for something other than, say, encoding ASCII characters. Including GBK, BIG5, Shift-JIS etc.
explode and other such PHP functions work on bytes, not characters.
What you do is to convert the string to UTF-8 using iconv(), then explode, then go back to GBK.
gxd305 at gmail dot com
17-Nov-2009 02:47
17-Nov-2009 02:47
when the encoding of $string is 'GBK' and $delimiter is '|' , the return value may be wrong.
for example:
<?php
$result = explode("|", "滕华弢|海青");
var_dump($result);
?>
and the result will be:
array (
0 => '滕华,
1 => '',
2 => '海青',
)
bcz "弢" 's GBK is '0x8f7c'. and "|" 's ASCII is '0x7c'.
So, all GBK-encoding characters include '7c' will lead to the error result.
nick dot brown at free dot fr
15-Oct-2009 12:47
15-Oct-2009 12:47
My application was running out of memory (my hosting company limits PHP to 32MB). I have a string containing between 100 and 20000 triplets, separated by a space, with each triplet consisting of three double-precision numbers, separated by commas. Total size of the biggest string, with 20000 triplets, is about 1MB.
The application needs to split the string into triplets, then split the triplet into numbers. In C, this would take up about 480K (20000 times 3 x 8 bytes) for the final array. The intermediate array of strings shouldn't be much bigger than the long string itself (1MB). And I expect some overhead from PHP, say 300% to allow for indexes etc.
Well, PHP5 manages to run out of memory *at the first stage* (exploding the string on the space character). I'm expecting to get an array of 20000 strings, but it needs more than 32MB to store it. Amazing.
The workaround was easy and had the bonus of producing faster code (I compared it on a 10000 triplet string). Since in any case I had to split up the numeric triplets afterwards, I decided to use preg_match_all() on the original string. Despite the fact that the resulting "matches" array contains more data per element than the result of explode() - because it stores the matched triplet, plus its component numbers - it takes up far less memory.
Moral: be careful when using explode() on big strings, as it can also explode your memory usage.
Jrg Wagner
12-Oct-2009 11:28
12-Oct-2009 11:28
Here is a very concise example for a quote aware explode - substrings in quotes (or another definable enclosure char) are not exploded.
An additional parameter allows to determine whether the enclosure chars should be preserved within the resulting array elements. Please note that as of PHP 5.3 the str_getcsv function offers a built-in way to do this!
<?php
function csv_explode($delim=',', $str, $enclose='"', $preserve=false){
$resArr = array();
$n = 0;
$expEncArr = explode($enclose, $str);
foreach($expEncArr as $EncItem){
if($n++%2){
array_push($resArr, array_pop($resArr) . ($preserve?$enclose:'') . $EncItem.($preserve?$enclose:''));
}else{
$expDelArr = explode($delim, $EncItem);
array_push($resArr, array_pop($resArr) . array_shift($expDelArr));
$resArr = array_merge($resArr, $expDelArr);
}
}
return $resArr;
}
?>
Anonymous
29-Sep-2009 12:20
29-Sep-2009 12:20
Note to the previous example: we can do the whole string->array conversion using explode() exclusively.
<?php
// converts pure string into a trimmed keyed array
function string_2_array( $string, $delimiter = ',', $kv = '=>')
{
if ($element = explode( $delimiter, $string ))
{
// create parts
foreach ( $element as $key_value )
{
// key -> value pair or single value
$atom = explode( $kv, $key_value );
if( trim($atom[1]) )
{
$key_arr[trim($atom[0])] = trim($atom[1]);
}
else
{
$key_arr[] = trim($atom[0]);
}
}
}
else
{
$key_arr = false;
}
return $key_arr;
}
?>
Anonymous
03-Sep-2009 04:18
03-Sep-2009 04:18
<?php
// converts pure string into a trimmed keyed array
function string2KeyedArray($string, $delimiter = ',', $kv = '=>') {
if ($a = explode($delimiter, $string)) { // create parts
foreach ($a as $s) { // each part
if ($s) {
if ($pos = strpos($s, $kv)) { // key/value delimiter
$ka[trim(substr($s, 0, $pos))] = trim(substr($s, $pos + strlen($kv)));
} else { // key delimiter not found
$ka[] = trim($s);
}
}
}
return $ka;
}
} // string2KeyedArray
$string = 'a=>1, b=>23 , $a, c=> 45% , true,d => ab c ';
print_r(string2KeyedArray($string));
?>
Array
(
[a] => 1
[b] => 23
[0] => $a
[c] => 45%
[1] => true
[d] => ab c
)
Anonymous
11-Aug-2009 07:55
11-Aug-2009 07:55
If you are exploding string literals in your code that have a dollar sign ($) in it, be sure to use single-quotes instead of double-quotes, since php will not spare any chance to interpret the variable-friendly characters after the dollar signs as variables, leading to unintended consequences, the most typical being missing characters.
<?php
$doubleAr = explode(" ", "The $quick brown fox");
$singleAr = explode(" ", 'The $quick brown fox');
echo $doubleAr[1]; // prints "";
echo $singleAr[1]; // prints "$quick";
?>
vzverev at nm dot ru
24-Jul-2009 04:33
24-Jul-2009 04:33
If you are going to use foreach after explode(), call reset() before foreach:
<?php
$arr = explode("\n", 'test \n test2 \n test3');
reset($arr);
foreach($arr as $line)
{ /* do something */ ; }
?>
marcus at synchromedia dot co dot uk
15-Jun-2009 03:50
15-Jun-2009 03:50
Just in case the comment about empty strings is not clear:
<?php
$a = array();
var_dump($a);
$s = implode("\n", $a);
var_dump($s);
$b = explode("\n", $s);
var_dump($b);
$b = preg_split('/\n/', $s,-1,PREG_SPLIT_NO_EMPTY);
var_dump($b);
?>
Results in:
array(0) {
}
string(0) ""
array(1) {
[0]=>
string(0) ""
}
array(0) {
}
i.e. exploding an empty string results in an array with one element. You can use preg_split to skip the empty item, but that may not be quite what you need should your array have empty elements intentionally.
SR
21-Apr-2009 04:50
21-Apr-2009 04:50
Keep in mind that explode() can return empty elements if the delimiter is immediately repeated twice (or more), as shown by the following example:
<?php
$foo = 'uno dos tres'; // two spaces between "dos" and "tres"
print_r(explode(' ', $foo));
?>
Array
(
[0] => uno
[1] => dos
[2] =>
[3] => tres
)
Needless to say this is definitely not intuitive and must be handled carefully.
Michael
19-Apr-2009 11:29
19-Apr-2009 11:29
Here's a simple script which uses explode() to check to see if an IP address is in an array (can be used as a ban-check, without needing to resort to database storage and queries).
<?php
function denied($one) {
$denied = array(
0 => '^255.255.255.255',
1 => '^255.250',
2 => '^255.255.250'
);
for ($i = 0 ; $i < sizeof($denied) ; $i++) {
if (sizeof(explode($denied[$i], '^' . $one . '$')) == 2) {
return true;
}
}
return false;
}
if (denied($_SERVER['REMOTE_ADDR'])) {
header('Location: denied.php');
}
?>
Navi
31-Mar-2009 02:03
31-Mar-2009 02:03
<?php
function my_explode($delim, $str, $lim = 1)
{
if ($lim > -2) return explode($delim, $str, abs($lim));
$lim = -$lim;
$out = explode($delim, $str);
if ($lim >= count($out)) return $out;
$out = array_chunk($out, count($out) - $lim + 1);
return array_merge(array(implode($delim, $out[0])), $out[1]);
}
?>
This function can assume `limit' parameter less than 0, for example:
<?php
print_r(my_explode('.', 'file.some.ext.jpg', -2));
?>
prints
Array
(
[0] => file.some.ext
[1] => jpg
)
adrian at bilsoftware dot com
23-Feb-2009 11:40
23-Feb-2009 11:40
<?php
function explode_escaped($delimiter, $string){
$exploded = explode($delimiter, $string);
$fixed = array();
for($k = 0, $l = count($exploded); $k < $l; ++$k){
if($exploded[$k][strlen($exploded[$k]) - 1] == '\\') {
if($k + 1 >= $l) {
$fixed[] = trim($exploded[$k]);
break;
}
$exploded[$k][strlen($exploded[$k]) - 1] = $delimiter;
$exploded[$k] .= $exploded[$k + 1];
array_splice($exploded, $k + 1, 1);
--$l;
--$k;
} else $fixed[] = trim($exploded[$k]);
}
return $fixed;
}
?>
Here's a function which explodes string with delimiter, but if delimiter is "escaped" by backslash, function won't split in that point. Example:
<?php
$result = explode_escaped(',', 'string, piece, group\, item\, item2, next\,asd');
print_r($result);
?>
Will give:
Array
(
[0] => string
[1] => piece
[2] => group, item, item2
[3] => next,asd
)
Elad Elrom
05-Dec-2008 06:02
05-Dec-2008 06:02
<?php
// Remove words if more than max allowed character are insert or add a string in case less than min are displayed
// Example: LimitText("The red dog ran out of thefence",15,20,"<br>");
function LimitText($Text,$Min,$Max,$MinAddChar) {
if (strlen($Text) < $Min) {
$Limit = $Min-strlen($Text);
$Text .= $MinAddChar;
}
elseif (strlen($Text) >= $Max) {
$words = explode(" ", $Text);
$check=1;
while (strlen($Text) >= $Max) {
$c=count($words)-$check;
$Text=substr($Text,0,(strlen($words[$c])+1)*(-1));
$check++;
}
}
return $Text;
}
?>
Nobody
17-Nov-2008 02:38
17-Nov-2008 02:38
A really better and shorter way to get extension is via:
<?php $extension = end(explode('.', $filename)); ?>
this will print the last part after the last dot :)
shaun
29-Aug-2008 09:24
29-Aug-2008 09:24
For anyone trying to get an array of key => value pairs from a query string, use parse_str. (Better alternative than the explode_assoc function listed way down the page unless you need different separators.)
pinkgothic at gmail dot com
15-Oct-2007 11:26
15-Oct-2007 11:26
coroa at cosmo-genics dot com mentioned using preg_split() instead of explode() when you have multiple delimiters in your text and don't want your result array cluttered with empty elements. While that certainly works, it means you need to know your way around regular expressions... and, as it turns out, it is slower than its alternative. Specifically, you can cut execution time roughly in half if you use array_filter(explode(...)) instead.
Benchmarks (using 'too many spaces'):
Looped 100000 times:
preg_split: 1.61789011955 seconds
filter-explode: 0.916578054428 seconds
Looped 10000 times:
preg_split: 0.162719011307 seconds
filter-explode: 0.0918920040131 seconds
(The relation is, evidently, pretty linear.)
Note: Adding array_values() to the filter-explode combination, to avoid having those oft-feared 'holes' in your array, doesn't remove the benefit, either. (For scale - the '9' becomes a '11' in the benchmarks above.)
Also note: I haven't tested anything other than the example with spaces - since djogo_curl at yahoo's note seems to imply that explode() might get slow with longer delimiters, I expect this would be the case here, too.
I hope this helps someone. :)
seventoes at gmail dot com
10-Dec-2006 04:49
10-Dec-2006 04:49
Note that explode, split, and functions like it, can accept more than a single character for the delimiter.
<?php
$string = "Something--next--something else--next--one more";
print_r(explode('--next--',$string));
?>
djogo_curl at yahoo
01-Dec-2004 01:50
01-Dec-2004 01:50
Being a beginner in php but not so in Perl, I was used to split() instead of explode(). But as split() works with regexps it turned out to be much slower than explode(), when working with single characters.
coroa at cosmo-genics dot com
16-Nov-2003 05:01
16-Nov-2003 05:01
To split a string containing multiple seperators between elements rather use preg_split than explode:
preg_split ("/\s+/", "Here are to many spaces in between");
which gives you
array ("Here", "are", "to", "many", "spaces", "in", "between");