Wordpress - 如何在我的页面中显示帖子内容 html？

Question

I'm new to WordPress I am trying to display the first 10 posts in the database with a shortcode with this code. It's just an experiment to learn.

function do_hello_world()
{
    global $wpdb;
    $result = $wpdb->get_results('SELECT post_content FROM wp_posts LIMIT 10');

    $content = "";

    for ($i = 0; $i < count($result); $i++) {
        $content = $content . $result[$i];
    }

    return $content;
}
add_shortcode('hello_world', 'do_hello_world');

But I get the following error on my page when the shortcode is added.

Notice: Array to string conversion in D:\Work\DGS\Cam_Rent\Site\wp-includes\shortcodes.php on line 325 Array

I checked in the database and post_content is a long text filled with HTML. Shouldn't this code make a string? My goal is to display the HTML from those posts on my page, how would I do that?

Answer 1

As said Mohammad Ashique Ali , it's better to not use directly wpdb, there is a lot of wordpress functions like wp_posts :
https://codex.wordpress.org/Function_Reference/get_posts

try this:

add_shortcode("hello_world", function ($attr, $content, $tag) {


    $posts = get_posts([
        "post_type" => "post",
        "posts_per_page" => 10,
    ]);


    $result = "";

    foreach ($posts as $post) {

        $result .= $post->post_content . "<hr/>";

    }


    return $result;

});

Answer 2

You can use Insert PHP Code Snippet plugin.

1. Install the plugin.
2. Then you got a sidebar menu like XYZ PHP Code.
3. Add a new snippet and write your code.
4. Insert this snippet to your page post and publish it.

Plugin link: https://wordpress.org/plugins/insert-php-code-snippet/

Answer 3

I checked in the database and post_content is a long text filled with HTML. Shouldn't this code make a string?

No.

If you use the print_r() function to see what the value of $result is, you'll get something like this:

Array
(
    [0] => stdClass Object
        (
            [post_content] => <!-- wp:paragraph -->
<p>Welcome to WordPress. This is your first post. Edit or delete it, then start writing!</p>
<!-- /wp:paragraph -->
        )

    ...

)

An array of objects .

The reason why you're getting that PHP warning is because you're trying to concatenate a string ( $content ) with an object ( $result[$i] , which is a stdClass Object ):

$content = $content . $result[$i];

To access the actual content from your posts (and fix the problem), change that line to:

$content = $content . $result[$i]->post_html;

Notice how now we're using the post_html property of the object to retrieve the HTML of the post.