PHP实例说明编写PHP代码的5个好习惯

<?php

function createRssHeader()
{
    return "<rss version=\"2.0\">" .
        "<channel>" .
        "<title>My Great Feed</title>" .
        "<link>http://www.example.com/feed.xml</link>" .
        "<description>The best feed in the world</description>" .
        "<language>en-us</language>" .
        "<pubDate>Tue, 20 Oct 2008 10:00:00 GMT</pubDate>" .
        "<lastBuildDate>Tue, 20 Oct 2008 10:00:00 GMT</lastBuildDate>" .
        "<docs>http://www.example.com/rss</docs>" .
        "<generator>MyFeed Generator</generator>" .
        "<managingEditor>editor@example.com</managingEditor>" .
        "<webMaster>webmaster@example.com</webMaster>" .
        "<ttl>5</ttl>";
}

function createRssFooter()
{
    return "</channel></rss>";
}

function createRssItem($title, $link, $desc, $date, $guid) 
{
    $item .= "<item>";
    $item .= "<title>" . $title . "</title>";
    $item .= "<link>" . $link . "</link>";
    $item .= "<description> " . $description . "</description>";
    $item .= "<pubDate>" . $date . "</pubDate>";
    $item .= "<guid>" . $guid . "</guid>";
    $item .= "</item>";
    return $item;
}

function getUserMaxStories($db_link, $default)
{
    $perfsQuery = sprintf("SELECT max_stories FROM user_perfs WHERE user= ''%s''",
            mysql_real_escape_string($user));

    $result = mysql_query($perfsQuery, $db_link);

    $max_stories = $default;

    if ($row = mysql_fetch_assoc($result)) {
        $max_stories = $row[''max_stories''];
    } 

    return $max_stories;
}

function writeRssFeed($user)
{
    // Get the DB connection information
    $settings = parse_ini_file("rss_server.ini");

    // look up the user''s preferences...
    $link = mysql_connect($settings[''db_host''], $settings[''user''], 
        $settings[''password'']) OR die(mysql_error());

    $max_stories = getUserMaxStories($link, 25);

    // go get my data
    $newsQuery = sprintf("SELECT * FROM stories WHERE post_date = ''%s''",
            mysql_real_escape_string(time()));

    $result = mysql_query($newsQuery, $link); 

    $feed = createRssHeader();

    $i = 0;
    // build the feed...
    while ($row = mysql_fetch_assoc($result)) {
        if ($i < $max_stories) {
            $title = $row[''title''];
            $link = $row[''link''];
            $description = $row[''description''];
            $date = $row[''date''];
            $guid = $row[''guid''];

            $feed .= createRssItem($title, $link, $description, $date, $guid);

            $i++;
        } else { 
            break;
        }
    }

    mysql_close($link);

    $feed .= createRssFooter();

    // write the feed out to the server...
    echo($feed);
}
?>