Associative array - sorting and traversing

Arrays example from a Well House Consultants training course
More on Arrays [link]

This example is described in the following article(s):
• Looking up a value by key - associative arrays / Hashes / Dictionaries - [link]

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This example references the following resources:
http://www.wellho.net/pix/dyr69.jpg

Source code: assoc.php Module: H106


<?php

# Illustation of an associative array in PHP

# An associative array can be keyed by any value - not just a sequential index

$nat_park = array();

$nat_park["Exmoor"] = 1001;
$nat_park["Dartmoor"] = 1;
$nat_park["Snowdonia"] = 20;
$nat_park["Peak District"] = 500;
$nat_park["Lake District"] = 500;
$nat_park["Cairngorms"] = 5000;

/* With apologies to the following which I left out ....

Brecon Beacons
Broads
Loch Lomond
New Forest
Northumberland
North York Moors
Pembrokeshire Coast
South Downs
Yorkshire Dales         */

ksort($nat_park);

$html = "";

foreach (array_keys($nat_park) as $parkname) {

/* Here are three ALTERNATIVE ways of choosing between two results in PHP */

# 1. Traditional "if" and "else"

        if ($nat_park[$parkname] != 1) {
                $word = "are";
        } else {
                $word = "was";
        }

# 2. The "ternary conditionsl"

        $word = ($nat_park[$parkname] != 1) ? "are" : "is";

# 3. Set a default and override if need be (using a lazy operator in this example)

        $word = "ARE";
        $nat_park[$parkname] != 1 or $word = "IS";

# You only need one of the three ;-)

        $html .= "There $word $nat_park[$parkname] deer in the $parkname National Park<br>";

# Or you could even write it directly into the results line ... option (4)!

        $html .= "There " .
                (($nat_park[$parkname] != 1) ? "are" : "is")
                . " $nat_park[$parkname] deer in the $parkname National Park<br>";
        }

?>
<html>
<head>
<title>Numbers of Deer in each of the UK National Parks</title>
</head>
<body>
<img src=http://www.wellho.net/pix/dyr69.jpg align=right hspace=5>The information
shown here is truely fictional - although the names used are indeed the names of UK
National Parks - it's an illustration of the use of an associative array in PHP.
<br /><br /><?= $html ?><br /><br clear="all" />
</body>
</html>

Learn about this subject

This module and example are covered on the following public courses:
* Learning to program in PHP
* PHP Programming
* Beginning PHP - weekend course / hobby / club / leisure users
* PHP Programming
* Learning to program in PHP
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