Step 3: Adding Page Numbers

In this section, we extend the browse( ) function to produce page numbers to permit direct access to the pages, removing the need for the user to repeatedly click the Previous or Next links to find a particular page or row. The extended fragment of browse( ) that produces the page links is shown in Example 5-11.

Example 5-11. Adding direct page access to browse( )

// (7a) Previous link code goes here

// Output the page numbers as links
// Count through the number of pages in the results
for($x=0, $page=1;
    $x<$rowsFound;
    $x+=ROWS, $page++)
   // Is this the current page?
   if ($x < $rowOffset ||
       $x > ($rowOffset + $numRowsToFetch - 1))
      // No, so print out a link
      echo "<a href=\"" . $scriptName .
           "?offset=" . rawurlencode($x) .
           "&amp;" . $browseString .
           "\">" . $page  . "</a> ";
      else
         // Yes, so don't print a link
         echo $page  . " ";

// (7b) Next link code goes here

The page number code consists of a for loop that works as follows:

The loop begins counting rows using the variable $x-starting at row zero-and pages using $page, starting on page one. The loop finishes when $x is equal to the number of rows in the query result set.
In the body of the loop, if the row $x isn't on the current page displayed in the HTML <table>, an embedded link is output that is marked with the page number $page. The link is to the script resource $scriptName, with the parameters in $browseString and an offset of the current value of $x. The current value of $x is the first row on the page numbered $page. Clicking on the link requests the script again and produces the results for $page that begin with the row with an offset of $x.

For example, if $x is row 220, and the $page is 11, the embedded link output by the code fragment is:
```
<a href="example.5-11.php? offset=220&amp;regionName=Margaret%20River">11</a>
```
If $x is a row on the currently displayed page, the code outputs the page number without the embedded hypertext link.

The case study of a generic browse( ) function is now complete. Additional features can be added, as discussed briefly in the next section.

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