A list of countries as well as cities:
Tokyo, Japan; Mexico City, Mexico; New York City, USA; Mumbai, India; Seoul, Korea; Shanghai, China; Lagos, Nigeria; Buenos Aires, Argentina; Cairo, Egypt; London, England.
Create an associative array, using the countries as keys, the cities as values. Create a form for the user, with the instructions Please choose a city:
Follow this request with a select field for the 10 cities, with the options created by looping through the array. When the user clicks the submit button, return the statement $city is in $country., where $city is the value chosen by the user, and $country is its key.
Tokyo, Japan; Mexico City, Mexico; New York City, USA; Mumbai, India; Seoul, Korea; Shanghai, China; Lagos, Nigeria; Buenos Aires, Argentina; Cairo, Egypt; London, England.
Create an associative array, using the countries as keys, the cities as values. Create a form for the user, with the instructions Please choose a city:
Follow this request with a select field for the 10 cities, with the options created by looping through the array. When the user clicks the submit button, return the statement $city is in $country., where $city is the value chosen by the user, and $country is its key.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html;charset=iso-8859-1" />
<title>Associative Array - Cities</title>
</head>
<body>
<h2>Large Cities Again<br /></h2>
<?php
//Create associative array with countries as keys, cities as values.
$cities=array (
"Japan" => "Tokyo",
"Mexico" => "Mexico City",
"USA" => "New York City",
"India" => "Mumbai",
"Korea" => "Seoul",
"China" => "Shanghai",
"Nigeria" => "Lagos",
"Argentina" => "Buenos Aires",
"Egypt" => "Cairo",
"UK" => "London"
);
//If form not submitted, display form.
if(!isset($_POST['submit'])){
?>
<form method="post" action="#">
<p>Please choose a city:</p>
<select name="city">
<?php
//Use array to create options for select field.
//Be sure to escape the quotes and include a line feed.
foreach($cities as $c){
echo "<option value=\"$c\">$c</option>\n";
}
?>
</select> <p />
<input type="submit" name="submit" value="Go">
</form>
<?php
//If form submitted, process input.
}else{
//Retrieve user response.
$city=$_POST['city'];
//Find corresponding key in associative array.
$country=array_search($city, $cities);
//Send the data back to the user.
echo "<p>$city is in $country.</p>" ;
}
?>
</body>
</html>
