php - 如何像 Wordpress 循环一样制作我自己的 while 循环？

Question

我是新手，也是 PHP 新手..

只是想知道如何像在 Wordpress 中一样制作我自己的灵活循环...注意我不是在谈论 wordpress..我想在我自己的 PHP 应用程序上实现它...

我们回顾一下WP中，有这样一段代码:

while (have_post() : thepost())// .. bla bla...

echo the_title();
echo the_content();

endwhile; // this is just an ilustration

你能弄清楚 have_post() 或 the_post() 是如何与数据库交互的吗？这样它们就可以循环..

谢谢..

Answer 1

WordPress 使用这些函数在遍历循环时修改的全局变量。例如:

var $posts = null;
var $post = null;
var $post_count = 0;
var $post_index = 0;

function have_post() {
    global $posts, $post_count, $post_index;

    $post_index = 0;

    // do a database call to retrieve the posts.
    $posts = mysql_query('select * from posts where ...');

    if ($posts) {
        $post_count = count($posts);
        return true;
    } else {
        $post_count = 0;
        return false;
    }
}

function thepost() {
    global $posts, $post, $post_count, $post_index;

    // make sure all the posts haven't already been looped through
    if ($post_index > $post_count) {
        return false;
    }

    // retrieve the post data for the current index
    $post = $posts[$post_index];

    // increment the index for the next time this method is called
    $post_index++;

    return $post;
}

function the_title() {
    global $post;
    return $post['title'];
}

function the_content() {
    global $post;
    return $post['content'];
}

不过，我肯定会推荐使用 OOP 风格编码而不是 WordPress。这将使变量在对象的实例中定义，而不是全局可访问。例如:

class Post {
    function __construct($title, $content) {
        $this->title = $title;
        $this->content = $content;
    }

    function getTitle() {
        return $title;
    }

    function getContent() {
        return $content;
    }
}

class Posts {
    var $postCount = 0;
    var $posts = null;

    function __construct($conditions) {
        $rs = mysql_query('select * from posts where $conditions...');

        if ($rs) {
            $this->postCount = count($rs);
            $this->posts = array();

            foreach ($rs as $row) {
                $this->posts[] = new Post($row['title'], $row['content']);
            }
        }
    }

    function getPostCount() {
        return $this->postCount;
    }

    function getPost($index) {
        return $this->posts[$index];
    }
}