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Unit 6: Building Blocks of PHP

[2] => 3 Notes
)

Array

(
[0] => 1

[1] => 2

[2] => 3
)

So, you can see that you can use both the array() construct and the $arr[key] notation to create
arrays. Usually, array() is used to declare arrays whose elements are known at compile-time,
and the $arr[key] notation is used when the elements are only computed at runtime. PHP also
supports a special notation, $arr[], where the key is not specified. When creating new array
offsets using this notation (fo example, using it as the l-value), the key is automatically assigned
as one more than the largest previous integer key.
Therefore, the previous example can be rewritten as follows:

$arr1 = array(1, 2, 3);

$arr2[] = 1;
$arr2[] = 2;

$arr2[] = 3;
The result is the same as in the previous example.

The same holds true for arrays with string keys:

$arr1 = array(“name” => “John”, “age” => 28);
$arr2[“name”] = “John”;

$arr2[“age”] = 28;
if ($arr1 == $arr2) {

print ‘$arr1 and $arr2 are the same’ . “\n”;

}
The message confirming the equality of both arrays is printed.

Reading Array Values

You can use the $arr[key] notation to read array values. The next few examples build on top
of the previous example:

print $arr2[“name”];

if ($arr2[“age”] < 35) {

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