Page 153 - Beginning PHP 5.3

Chapter 6: Arrays
Now you can rewrite the example that used each() with a while loop in the previous section
( “ Stepping Through an Array ” ) to use a foreach loop instead:
< !DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Strict//EN”
“http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd” >
< html xmlns=”http://www.w3.org/1999/xhtml” xml:lang=”en” lang=”en” >
< head >
< title > Using foreach < /title >
< link rel=”stylesheet” type=”text/css” href=”common.css” / >
< /head >
< body >
< h1 > Using foreach < /h1 >

< dl >
< ?php

$myBook = array( “title” = > “The Grapes of Wrath”,
“author” = > “John Steinbeck”,
“pubYear” = > 1939 );
foreach ( $myBook as $key = > $value ) {
echo “ < dt > $key < /dt > ”;
echo “ < dd > $value < /dd > ”;
}
? >

< /dl >
< /body >
< /html >
This code produces the same list of keys and values as shown in Figure 6-3 .

Altering Array Values with foreach
When using foreach , the values you work with inside the loop are copies of the values in the array
itself. This means that if you change the value given to you by foreach , you ’ re not affecting the
corresponding value in the original array. The following example code illustrates this:

$authors = array( “Steinbeck”, “Kafka”, “Tolkien”, “Dickens” );
// Displays “Steinbeck Kafka Hardy Dickens”;
foreach ( $authors as $val ) {
if ( $val == “Tolkien” ) $val = “Hardy”;
echo $val . “ “;
}
echo “ < br/ > ”;

// Displays “Array ( [0] = > Steinbeck [1] = > Kafka [2] = > Tolkien [3] = >
Dickens )”

print_r ( $authors );
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