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Содержание
  1. array_replace_recursive
  2. Parameters
  3. Return Values
  4. Examples
  5. See Also
  6. User Contributed Notes 7 notes
  7. array_replace
  8. Список параметров
  9. Возвращаемые значения
  10. Примеры
  11. Смотрите также

array_replace_recursive

array_replace_recursive() replaces the values of array with the same values from all the following arrays. If a key from the first array exists in the second array, its value will be replaced by the value from the second array. If the key exists in the second array, and not the first, it will be created in the first array. If a key only exists in the first array, it will be left as is. If several arrays are passed for replacement, they will be processed in order, the later array overwriting the previous values.

array_replace_recursive() is recursive : it will recurse into arrays and apply the same process to the inner value.

When the value in the first array is scalar, it will be replaced by the value in the second array, may it be scalar or array. When the value in the first array and the second array are both arrays, array_replace_recursive() will replace their respective value recursively.

Parameters

The array in which elements are replaced.

Arrays from which elements will be extracted.

Return Values

Examples

Example #1 array_replace_recursive() example

$base = array( ‘citrus’ => array( «orange» ) , ‘berries’ => array( «blackberry» , «raspberry» ), );
$replacements = array( ‘citrus’ => array( ‘pineapple’ ), ‘berries’ => array( ‘blueberry’ ));

$basket = array_replace_recursive ( $base , $replacements );
print_r ( $basket );

$basket = array_replace ( $base , $replacements );
print_r ( $basket );
?>

The above example will output:

Array ( [citrus] => Array ( [0] => pineapple ) [berries] => Array ( [0] => blueberry [1] => raspberry ) ) Array ( [citrus] => Array ( [0] => pineapple ) [berries] => Array ( [0] => blueberry ) )

Example #2 array_replace_recursive() and recursive behavior

$base = array( ‘citrus’ => array( «orange» ) , ‘berries’ => array( «blackberry» , «raspberry» ), ‘others’ => ‘banana’ );
$replacements = array( ‘citrus’ => ‘pineapple’ , ‘berries’ => array( ‘blueberry’ ), ‘others’ => array( ‘litchis’ ));
$replacements2 = array( ‘citrus’ => array( ‘pineapple’ ), ‘berries’ => array( ‘blueberry’ ), ‘others’ => ‘litchis’ );

$basket = array_replace_recursive ( $base , $replacements , $replacements2 );
print_r ( $basket );

The above example will output:

Array ( [citrus] => Array ( [0] => pineapple ) [berries] => Array ( [0] => blueberry [1] => raspberry ) [others] => litchis )

See Also

  • array_replace() — Replaces elements from passed arrays into the first array
  • array_merge_recursive() — Merge one or more arrays recursively

User Contributed Notes 7 notes

Nice that this function finally found its was to the PHP core! If you want to use it also with older PHP versions before 5.3.0, you can define it this way:

if (! function_exists ( ‘array_replace_recursive’ ))
function array_replace_recursive ( $array , $array1 )
function recurse ( $array , $array1 )
foreach ( $array1 as $key => $value )
// create new key in $array, if it is empty or not an array
if (!isset( $array [ $key ]) || (isset( $array [ $key ]) && ! is_array ( $array [ $key ])))
$array [ $key ] = array();
>

// overwrite the value in the base array
if ( is_array ( $value ))
$value = recurse ( $array [ $key ], $value );
>
$array [ $key ] = $value ;
>
return $array ;
>

// handle the arguments, merge one by one
$args = func_get_args ();
$array = $args [ 0 ];
if (! is_array ( $array ))
return $array ;
>
for ( $i = 1 ; $i < count ( $args ); $i ++)
if ( is_array ( $args [ $i ]))
$array = recurse ( $array , $args [ $i ]);
>
>
return $array ;
>
>
?>

I called this function array_merge_recursive_overwrite() in my older projects, but array_replace_recursive() sounds quite better while they do the same.

If you implemented such a compatible function before and don’t want to refactor all your code, you can update it with the following snippet to use the native (and hopefully faster) implementation of PHP 5.3.0, if available. Just start your function with these lines:

// as of PHP 5.3.0 array_replace_recursive() does the work for us
if ( function_exists ( ‘array_replace_recursive’ ))
return call_user_func_array ( ‘array_replace_recursive’ , func_get_args ());
>
?>

Note that function will NOT replace a sub-tree from you $array1 if its value in $array2 is an empty array.
Even tho the key for this dimension is technically ‘set’.

(I suppose it treats it as just another recursive level to dive in, finding no key to compare, backtracking while leaving this sub-tree alone)

$array1 = [‘first’ => [‘second’ => ‘hello’]];
$array2 = [‘first’ => []];
$result = array_replace_recursive($array1, $array2);

$result is still: [‘first’ => [‘second’ => ‘hello’]].

It seemed to me that the first argument is passed by reference, so it will contain the results of this operation, but experiment shows that this is not true. The array value from the first argument is modified by each succeeding argument, and the result is returned to the caller. The array passed as the first argument is not modified.

This is a fairly concise version which does not rely on traditional recursion:

function array_replace_recursive ( $base , $replacements )
<
foreach ( array_slice ( func_get_args (), 1 ) as $replacements ) <
$bref_stack = array(& $base );
$head_stack = array( $replacements );

unset( $bref_stack [ key ( $bref_stack )]);

foreach ( array_keys ( $head ) as $key ) <
if (isset( $key , $bref ) && is_array ( $bref [ $key ]) && is_array ( $head [ $key ])) <
$bref_stack [] = & $bref [ $key ];
$head_stack [] = $head [ $key ];
> else <
$bref [ $key ] = $head [ $key ];
>
>
> while( count ( $head_stack ));
>

Note that the use of the word «replace» in the function’s description is a bit misleading. as none of the parameters are passed by reference, it does not actually replace anything. this simply describes from which parameter the resulting values come.

This might help out people who don’t have 5.3 running:

// Joins two or more arrays together recursively; key/value pairs of the first
// array are replaced with key/value pairs from the subsequent arrays. Any
// key/value pair not present in the first array is added to the final array
function array_join ()
<
// Get array arguments
$arrays = func_get_args ();

// Define the original array
$original = array_shift ( $arrays );

// Loop through arrays
foreach ( $arrays as $array )
<
// Loop through array key/value pairs
foreach ( $array as $key => $value )
<
// Value is an array
if ( is_array ( $value ))
<
// Traverse the array; replace or add result to original array
$original [ $key ] = array_join ( $original [ $key ], $array [ $key ]);
>

// Value is not an array
else
<
// Replace or add current value to original array
$original [ $key ] = $value ;
>
>
>

// Return the joined array
return $original ;
>

If you came here looking for a function to recursively find and replace (scalar) values in an array (also recurses through objects):

define ( ‘RECURSIVE_REPLACE_MARKER’ , ‘recursive_replace_r47yr74yr7623t74r3645236rtvghdcbnsgxbt67g5e21873891’ );
/**
* Recursively replaces scalar values in objects and arrays. The passed array or object is altered in place.
* @param mixed $data An object or array.
* @param mixed $find The scalar value to find.
* @param mixed $replace The value to replace with (need not be a scalar).
*/
function recursive_replace (& $data , $find , $replace ) if( is_array ( $data )) if (!isset( $data [ RECURSIVE_REPLACE_MARKER ])) $data [ RECURSIVE_REPLACE_MARKER ] = TRUE ;
foreach( $data as $key => $val ) if( is_array ( $data [ $key ]) || is_object ( $data [ $key ])) recursive_replace ( $data [ $key ], $find , $replace );
>
else if( $data [ $key ] === $find ) $data [ $key ] = $replace ;
>
>
>
unset( $data [ RECURSIVE_REPLACE_MARKER ]);
>
>
elseif ( is_object ( $data )) if (!isset( $data -> RECURSIVE_REPLACE_MARKER )) $data -> RECURSIVE_REPLACE_MARKER = TRUE ;
foreach( $data as $key => $val ) if( is_array ( $data -> $key ) || is_object ( $data -> $key )) recursive_replace ( $data -> $key , $find , $replace );
>else if( $data -> $key === $find ) $data -> $key = $replace ;
>
>
>
unset( $data -> RECURSIVE_REPLACE_MARKER );
>
>
>
?>

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