PHP: explode - Manual (original) (raw)
(PHP 4, PHP 5, PHP 7, PHP 8)
explode — Split a string by a string
Description
Parameters
separator
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.
Note:
Prior to PHP 8.0, implode() accepted its parameters in either order.explode() has never supported this: you must ensure that the
separatorargument comes before thestringargument.
Return Values
Returns an array of strings created by splitting the string parameter on boundaries formed by the separator.
If separator is an empty string (""),explode() throws a ValueError. If separator contains a value that is not contained in string and a negativelimit is used, then an empty array will be returned, otherwise an array containingstring will be returned. If separator values appear at the start or end of string, said values will be added as an empty array value either in the first or last position of the returned array respectively.
Changelog
| Version | Description |
|---|---|
| 8.0.0 | explode() will now throw ValueError when separator parameter is given an empty string (""). Previously, explode() returned false instead. |
Examples
Example #1 explode() examples
`<?php
// Example 1
$pizza = "piece1 piece2 piece3 piece4 piece5 piece6"; pieces=explode("",pieces = explode(" ", pieces=explode("",pizza);
echo $pieces[0], PHP_EOL; // piece1
echo $pieces[1], PHP_EOL; // piece2
// Example 2
$data = "foo:*:1023:1000::/home/foo:/bin/sh";
list($user, pass,pass, pass,uid, gid,gid, gid,gecos, home,home, home,shell) = explode(":", $data);
echo $user, PHP_EOL; // foo
echo $pass, PHP_EOL; // *
?>`
Example #2 explode() return examples
<?php /* A string that doesn't contain the delimiter will simply return a one-length array of the original string. */ $input1 = "hello"; $input2 = "hello,there"; $input3 = ','; var_dump( explode( ',', $input1 ) ); var_dump( explode( ',', $input2 ) ); var_dump( explode( ',', $input3 ) );?>
The above example will output:
array(1) ( [0] => string(5) "hello" ) array(2) ( [0] => string(5) "hello" [1] => string(5) "there" ) array(2) ( [0] => string(0) "" [1] => string(0) "" )
Example #3 limit parameter examples
<?php $str = 'one|two|three|four';// positive limit print_r(explode('|', $str, 2));// negative limit 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
- mb_split() - Split multibyte string using regular expression
- str_word_count() - Return information about words used in a string
- strtok() - Tokenize string
- implode() - Join array elements with a string
Found A Problem?
3 years ago
Note that an empty input string will still result in one element in the output array. This is something to remember when you are processing unknown input.
For example, maybe you are splitting part of a URI by forward slashes (like "articles/42/show" => ["articles", "42", "show"]). And maybe you expect that an empty URI will result in an empty array ("" => []). Instead, it will contain one element, with an empty string:
<?php
$uri = ''; <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>p</mi><mi>a</mi><mi>r</mi><mi>t</mi><mi>s</mi><mo>=</mo><mi>e</mi><mi>x</mi><mi>p</mi><mi>l</mi><mi>o</mi><mi>d</mi><mi>e</mi><msup><mo stretchy="false">(</mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><msup><mi mathvariant="normal">/</mi><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">parts = explode('/', </annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8095em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">p</span><span class="mord mathnormal">a</span><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="mord mathnormal">t</span><span class="mord mathnormal">s</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:1.0019em;vertical-align:-0.25em;"></span><span class="mord mathnormal">e</span><span class="mord mathnormal">x</span><span class="mord mathnormal" style="margin-right:0.01968em;">pl</span><span class="mord mathnormal">o</span><span class="mord mathnormal">d</span><span class="mord mathnormal">e</span><span class="mopen"><span class="mopen">(</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mord"><span class="mord">/</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mpunct">,</span></span></span></span>uri);
var_dump($parts);
?>
Will output:
array(1) {
[0]=>
string(0) ""
}
And not:
array(0) {
}2 years ago
If your data is smaller than the expected count with the list expansion:
<?php
$data = "foo:*:1023:1000::/home/foo:/bin/sh";
list($user, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>p</mi><mi>a</mi><mi>s</mi><mi>s</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">pass, </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">a</span><span class="mord mathnormal">ss</span><span class="mpunct">,</span></span></span></span>uid, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>g</mi><mi>i</mi><mi>d</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">gid, </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" style="margin-right:0.03588em;">g</span><span class="mord mathnormal">i</span><span class="mord mathnormal">d</span><span class="mpunct">,</span></span></span></span>gecos, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>h</mi><mi>o</mi><mi>m</mi><mi>e</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">home, </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">h</span><span class="mord mathnormal">o</span><span class="mord mathnormal">m</span><span class="mord mathnormal">e</span><span class="mpunct">,</span></span></span></span>shell,$nu) = explode(":", $data);
?>
The result is a warning not an error:
PHP Warning: Undefined array key 7 in ...
The solution is to pad the array to the expected length:
<?php
$data = "foo:*:1023:1000::/home/foo:/bin/sh";
list($user, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>p</mi><mi>a</mi><mi>s</mi><mi>s</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">pass, </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">a</span><span class="mord mathnormal">ss</span><span class="mpunct">,</span></span></span></span>uid, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>g</mi><mi>i</mi><mi>d</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">gid, </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" style="margin-right:0.03588em;">g</span><span class="mord mathnormal">i</span><span class="mord mathnormal">d</span><span class="mpunct">,</span></span></span></span>gecos, <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>h</mi><mi>o</mi><mi>m</mi><mi>e</mi><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">home, </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">h</span><span class="mord mathnormal">o</span><span class="mord mathnormal">m</span><span class="mord mathnormal">e</span><span class="mpunct">,</span></span></span></span>shell,$nu) = array_pad( explode(":", $data), 8, "");
// where 8 is the count of the list arguments
?>4 years ago
Be careful, while most non-alphanumeric data types as input strings return an array with an empty string when used with a valid separator, true returns an array with the string "1"!
var_dump(explode(',', null)); //array(1) { [0]=> string(0) "" }
var_dump(explode(',', false)); //array(1) { [0]=> string(0) "" }
var_dump(explode(',', true)); //array(1) { [0]=> string(1) "1" }3 years ago
If you want to directly take a specific value without having to store it in another variable, you can implement the following:
$status = 'Missing-1';
echo <span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>s</mi><mi>t</mi><mi>a</mi><mi>t</mi><mi>u</mi><msub><mi>s</mi><mi>o</mi></msub><mi>n</mi><mi>l</mi><mi>y</mi><mo>=</mo><mi>e</mi><mi>x</mi><mi>p</mi><mi>l</mi><mi>o</mi><mi>d</mi><mi>e</mi><msup><mo stretchy="false">(</mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><msup><mo>−</mo><mo mathvariant="normal" lspace="0em" rspace="0em">′</mo></msup><mo separator="true">,</mo></mrow><annotation encoding="application/x-tex">status_only = explode('-', </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">s</span><span class="mord mathnormal">t</span><span class="mord mathnormal">a</span><span class="mord mathnormal">t</span><span class="mord mathnormal">u</span><span class="mord"><span class="mord mathnormal">s</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: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">o</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">n</span><span class="mord mathnormal" style="margin-right:0.01968em;">l</span><span class="mord mathnormal" style="margin-right:0.03588em;">y</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:1.0019em;vertical-align:-0.25em;"></span><span class="mord mathnormal">e</span><span class="mord mathnormal">x</span><span class="mord mathnormal" style="margin-right:0.01968em;">pl</span><span class="mord mathnormal">o</span><span class="mord mathnormal">d</span><span class="mord mathnormal">e</span><span class="mopen"><span class="mopen">(</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mord"><span class="mbin">−</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mpunct">,</span></span></span></span>status)[0];
// Missing