Assign the values “Cat”, “Dog”, and “Horse” to the variables $a, $b, and $c, respectively.
| <?php $a = “Original”; $my_array = array(“a” => “Cat”,“b” => “Dog”, “c” => “Horse”); extract($my_array); echo “\$a = $a; \$b = $b; \$c = $c”; ?> |
The extract() function imports variables from an array into the local symbol table.
It uses the array keys as variable names and the values as the corresponding variable values, creating a variable for each element in the current symbol table.
The function returns the number of variables successfully extracted.
| extract(array, extract_rules, prefix) |
|
Parameter |
Description |
|
array |
Required. Specifies the array to use. |
|
extract_rules |
Optional. The extract() function checks for invalid variable names and collisions with existing variable names. This parameter specifies how invalid and colliding names are treated. Possible values:
EXTR_REFS – Extracts variables as references. The imported variables are still referencing the values of the array parameter |
|
prefix |
Optional. If EXTR_PREFIX_SAME, EXTR_PREFIX_ALL, EXTR_PREFIX_INVALID, or EXTR_PREFIX_IF_EXISTS are used in the extract_rules parameter, a prefix must be specified.
This parameter sets the prefix, which is automatically separated from the array key by an underscore. |
|
Return Value: |
Returns the number of variables extracted on success |
|
PHP Version: |
4+ |
|
PHP Changelog: |
The extract_rules value EXTR_REFS was added in PHP 4.3. The extract_rules values EXTR_IF_EXISTS and EXTR_PREFIX_IF_EXISTS were added in PHP 4.2. As of PHP 4.0.5, this function now returns the number of variables extracted. The extract_rules value EXTR_PREFIX_INVALID was added in PHP 4.0.5. As of PHP 4.0.5, the extract_rules value EXTR_PREFIX_ALL now includes numeric variables as well. |
Using all parameters:
| <?php $a = “Original”; $my_array = array(“a” => “Cat”, “b” => “Dog”, “c” => “Horse”); extract($my_array, EXTR_PREFIX_SAME, “dup”); echo “\$a = $a; \$b = $b; \$c = $c; \$dup_a = $dup_a”; ?> |