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Unit 6: Building Blocks of PHP

print “ is of age “; Notes
print $person[“value”];

This prints

John is of age 28
When we explain how the list() construct works, you will understand why offsets 0 and 1 also
exist.

list() The list() construct is a way of assigning multiple array offsets to multiple variables in
one statement:

list($var1, $var2, ...) = $array;

The first variable in the list is assigned the array value at offset 0, the second is assigned offset 1,
and so on. Therefore, the list() construct translates into the following series of PHP statements:
$var1 = $array[0];

$var2 = $array[1];
...

As previously mentioned, the indexes 0 and 1 returned by each() are used by the list() construct.
You can probably already guess how the combination of list() and each() work. Consider the
highlighted line from the previous $players traversal example:
$players = array(“John”, “Barbara”, “Bill”, “Nancy”);

reset($players);
while (list($key, $val) = each($players)) {

print “#$key = $val\n”;

}
What happens in the boldfaced line is that during every loop iteration, each() returns the current
position’s key/value pair array, which, when examined with print_r(), is the following array:

Array
(

[1] => John

[value] => John
[0] => 0

[key] => 0
)

Then, the list() construct assigns the array’s offset 0 to $key and offset 1

to $val.

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