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    explode

    (PHP 4, PHP 5, PHP 7, PHP 8)

    explode — Split a string by a string

    Description

    explode(string $separator, string $string, int $limit = PHP_INT_MAX): array

    Returns an array of strings, each of which is a substring of string formed by splitting it on boundaries formed by the string separator.

    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 separator argument comes before the string argument.

    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 negative limit is used, then an empty array will be returned, otherwise an array containing string 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(" ", $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 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

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    User Contributed Notes 4 notes

    up
    29
    Gerben
    2 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     = '';
    $parts = explode('/', $uri);
    var_dump($parts);

    ?>

    Will output:

    array(1) {
    [0]=>
    string(0) ""
    }

    And not:

    array(0) {
    }
    up
    9
    marc
    1 year 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, $pass, $uid, $gid, $gecos, $home, $shell,$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, $pass, $uid, $gid, $gecos, $home, $shell,$nu) = array_pad( explode(":", $data), 8, "");
    // where 8 is the count of the list arguments
    ?>
    up
    11
    bocoroth
    3 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" }
    up
    0
    Alejandro-Ihuit
    2 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 $status_only = explode('-', $status)[0];

    // Missing
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