PHP4 Practical Application (6)

Now, you've learned that PHP allows you to nest conditional statements. However, if you look at the example that is used to demonstrate this concept, you will agree that it is both complex and frightening.


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<?

if ($day = = "Thursday")
{
if ($time = = "12")
{
if ($place = = "Italy")
{
$lunch = "pasta";
}
}
}

?>
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Fortunately, in addition to the comparison operators we have been able to use without any restrictions, PHP also provides a number of logical operators that allow you to assemble conditional statement descriptions. These are clearly illustrated in the table below:


Assume $delta = 12 and $omega = 9

Operator
Significance
Example
Results

&&
and
$delta = = $gamma && $delta > $omega
True

$delta && $omega < $omega
False

||
OR
$delta = = $gamma | | $delta < $omega
True

$delta > $gamma | | $delta < $omega
False

!
Not
! $delta
False

< =
Less than or equal to
$delta < = $omega
False


Well, we can rewrite the code for the above example with the logical operator, and you see, is the following statement simpler?

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<?

if ($day = = "Thursday" && $time = = "" && $place = = "Italy")
{
$lunch = "pasta";
}
--------------------------------------------------------------------------------
Is it simple and elegant? Yes