ajax load more posts, wp_create_nonce, Votes Post, randon posts (ok)

Ví dụ 1: Không sử dụng wp_create_nonce

Bước 1: Trong file index.php
<?php
/**
 * The main template file
 *
 * This is the most generic template file in a WordPress theme
 * and one of the two required files for a theme (the other being style.css).
 * It is used to display a page when nothing more specific matches a query.
 * E.g., it puts together the home page when no home.php file exists.
 *
 * @link https://codex.wordpress.org/Template_Hierarchy
 *
 * @package WordPress
 * @subpackage Twenty_Seventeen
 * @since 1.0
 * @version 1.0
 */

get_header(); ?>

<div class="wrap">
    <div id="primary" class="content-area">
        <main id="main" class="site-main" role="main">
            <?php
            if ( have_posts() ) :
                while ( have_posts() ) : the_post();
                    get_template_part( 'template-parts/post/content', get_post_format() );
                endwhile;
            else :
                get_template_part( 'template-parts/post/content', 'none' );
            endif;
            ?>
        </main>
        <?php
            global $wp_query;
            if (  $wp_query->max_num_pages > 1 ) echo '<div class="misha_loadmore">More posts</div>';
        ?>
    </div>
</div>
<?php get_footer();
Bước 2:
// Ajax lionel
function misha_my_load_more_scripts() {
	global $wp_query;
	wp_enqueue_script('jquery');
	wp_register_script( 'my_loadmore', get_stylesheet_directory_uri() . '/assets/js/myloadmore.js', array('jquery') );
	wp_localize_script( 'my_loadmore', 'misha_loadmore_params', array(
			'ajaxurl' => admin_url('admin-ajax.php'),
			'posts' => json_encode($wp_query->query_vars),
			'current_page' => get_query_var( 'paged' ) ? get_query_var('paged') : 1,
			'max_page' => $wp_query->max_num_pages
		) 
	);
 	wp_enqueue_script( 'my_loadmore' );
}
add_action( 'wp_enqueue_scripts', 'misha_my_load_more_scripts' );
function misha_loadmore_ajax_handler(){
	$args = json_decode( stripslashes( $_POST['query'] ), true );
	$args['paged'] = $_POST['page'] + 1;
	$args['post_status'] = 'publish';
	query_posts( $args );
	if( have_posts() ) :
		while( have_posts() ): the_post();
			get_template_part( 'template-parts/post/content', get_post_format() );
		endwhile;
	endif;
	die;
}
add_action('wp_ajax_loadmore', 'misha_loadmore_ajax_handler');
add_action('wp_ajax_nopriv_loadmore', 'misha_loadmore_ajax_handler');
Bước 3:
jQuery(document).ready(function($) {
	$('.misha_loadmore').click(function(){
		var button = $(this);
		var  data = {
			'action': 'loadmore',
			'query': misha_loadmore_params.posts,
			'page' : misha_loadmore_params.current_page
		};
		$.ajax({
			url : misha_loadmore_params.ajaxurl,
			data : data,
			type : 'POST',
			beforeSend : function ( xhr ) {
				button.text('Loading...');
			},
			success : function( data ){
				if( data ) { 
					button.text( 'More posts' ).prev().before(data);
					misha_loadmore_params.current_page++;
					if ( misha_loadmore_params.current_page == misha_loadmore_params.max_page ) 
						button.remove();
				} else {
					button.remove();
				}
			}
		});
	});
});

Ví dụ 2: Có sử dụng wp_create_nonce

https://functions.phpfunctions.php

define("THEMEAJAX",admin_url('admin-ajax.php'));
add_action('wp_ajax_load_posts_by_ajax','load_posts_by_ajax');
add_action('wp_ajax_nopriv_load_posts_by_ajax','load_posts_by_ajax');
function load_posts_by_ajax() {
	check_ajax_referer( 'load_more_posts','security' );
	$paged = $_POST['page'];
	$args = array(
		'post_type' => 'post',
		'post_status'=>'publish',
		'posts_per_page' =>'2',
		'paged'=>$paged
	);
	$my_posts = new WP_Query($args);
	if($my_posts->have_posts())  :
	?>
	<?php while ($my_posts->have_posts()) :$my_posts->the_post() ?>
		<h2><?php the_title(); ?></h2>
	<?php
	endwhile;
	endif;
	wp_die( );
}

https://index.phpindex.php

<?php
/**
 * The main template file
 *
 * This is the most generic template file in a WordPress theme
 * and one of the two required files for a theme (the other being style.css).
 * It is used to display a page when nothing more specific matches a query.
 * E.g., it puts together the home page when no home.php file exists.
 *
 * @link https://codex.wordpress.org/Template_Hierarchy
 *
 * @package WordPress
 * @subpackage Twenty_Seventeen
 * @since 1.0
 * @version 1.0
 */

get_header(); ?>

<div class="wrap">
  <div id="primaryy" class="content-areaa">
    <main id="main" class="my-posts" role="mainn">

      <?php
      if ( have_posts() ) :

        /* Start the Loop */
        while ( have_posts() ) : the_post();
          ?>
          <h2><?php the_title(); ?></h2>
          <?php
          the_excerpt();
        endwhile;
      endif;
      ?>

    </main><!-- #main -->
    <a href="javascript:void(0)" id = "loadmore" class="loadmore" data-hue="<?php echo THEMEAJAX;?>">Load More</a>
  </div><!-- #primary -->
  <script>
      var url = jQuery("#loadmore").attr('data-hue');
      var page = 2;
      jQuery(document).ready(function($) {
        $('body').on('click','.loadmore',function() {
          var data = {
            'action':"load_posts_by_ajax",
            'page':page,
            'security':'<?php echo wp_create_nonce( "load_more_posts" );?>'
          }
          $.post(url,data,function(response) {
            $('.my-posts').append(response);
            page++;
          });
        });
      });
  </script>
</div><!-- .wrap -->

<?php get_footer();

Ví dụ 3: Một cách viết khác 3 (Dùng scroll)

<!-- Bước 1 -->
	<?php  
		function shapeSpace_frontend_scripts() {
			global $wp_query;
			wp_enqueue_style( 'style-name',get_stylesheet_uri());
			wp_enqueue_script('jquery');
			wp_register_script( 'lionel', get_template_directory_uri() .'/assets/js/custom.js' , array('jquery'), false, true);
			wp_localize_script( 'lionel','lionel_loadmore_params' , array(
					'ajaxurl' => admin_url('admin-ajax.php'),
					'posts' => json_encode($wp_query->query_vars),
					'current_page' => get_query_var("paged") ? get_query_var("paged") : 1,
					'maxpage' => $wp_query->max_num_pages
				) 
			);
			wp_enqueue_script('lionel');
		}
		add_action('wp_enqueue_scripts', 'shapeSpace_frontend_scripts');
		// Lionel 2
		function lionel_loadmore_ajax_handler(){
			$args = json_decode( stripslashes( $_POST['query'] ), true );
			$args['paged'] = $_POST['page'] + 1; // we need next page to be loaded
			$args['post_status'] = 'publish';
			query_posts( $args );
			if( have_posts() ) :
				while( have_posts() ): the_post();
					get_template_part( 'template-parts/post/content', get_post_format() );
				endwhile;
			endif;
			die;
		}
		add_action('wp_ajax_loadmore', 'lionel_loadmore_ajax_handler');
	?>
<!-- Bước 2  -->
	<script>
		jQuery(function($){
		    var canBeLoaded = true, // this param allows to initiate the AJAX call only if necessary
		    bottomOffset = 1080; // the distance (in px) from the page bottom when you want to load more posts
		    $(window).scroll(function(){
		        var data = {
		            'action': 'loadmore',
		            'query': lionel_loadmore_params.posts,
		            'page' : lionel_loadmore_params.current_page
		        };
		        if( $(document).scrollTop() > ( $(document).height() - bottomOffset ) && canBeLoaded == true ){
		            $.ajax({
		                url : lionel_loadmore_params.ajaxurl,
		                data:data,
		                type:'POST',
		                beforeSend: function( xhr ){
		                    canBeLoaded = false; 
		                },
		                success:function(data){
		                    if( data ) {
		                        lionel_loadmore_params.current_page++;
		                        if(lionel_loadmore_params.current_page <= lionel_loadmore_params.maxpage) {
		                            $('#main').find('article:last-of-type').after( data );
		                            canBeLoaded = true;
		                        }
		                    }
		                }
		            });
		        }
		    });
		});
	</script>
<!-- Bước 3 -->
<?php get_header(); ?>
	<div class="wrap">
	    <div id="primary" class="content-area">
	        <main id="main" class="site-main" role="main">
	            <?php
	                if ( have_posts() ) :
	                    while ( have_posts() ) : the_post();
	                        get_template_part( 'template-parts/post/content', get_post_format() );
	                    endwhile;
	                endif;
	            ?>
	        </main>
	    </div>
	</div>
<?php get_footer(); ?>
<!-- Bước 4 file content.php -->
	<article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
		<header class="entry-header">
			<?php
				the_title( '<h1 class="entry-title">', '</h1>' );
			?>
		</header>
		<div class="entry-content">
			<?php
				the_content( sprintf(
					__( 'Continue reading<span class="screen-reader-text sss"> "%s"</span>', 'twentyseventeen'), get_the_title()
				) );
			?>
			<!-- Kết quả như này -->
			<!-- 
				<p>
					<a href="http://localhost/hoang/wordpress/2018/10/21/bai-viet-so-5-2/#more-45" class="more-link">
						Continue reading
						<span class="screen-reader-text sss"> "Bài viết số 6"</span>
					</a>
				</p> 
			-->
		</div>
	</article>

Ví dụ 4: More ajax toan tap

https://functions.phpfunctions.php

<?php  
add_action( 'wp_enqueue_scripts', 'mfnch_enqueue_styles', 101 );
function mfnch_enqueue_styles() {
    wp_enqueue_script( 'my_voter_script_obj', LIONELURICHILD_THEME_URI . '/assets/js/ajaxmp.js',array('jquery'), null, true);
    wp_localize_script( 'my_voter_script_obj', 'lionelajax', array( 'url' => admin_url( 'admin-ajax.php' ))); 
}
add_action('wp_ajax_load_posts_by_ajax','load_posts_by_ajax');
add_action('wp_ajax_nopriv_load_posts_by_ajax','load_posts_by_ajax');
function load_posts_by_ajax() {
    $paged = $_POST['page'];
    $args = array(
        'post_type' => 'post',
        'post_status'=>'publish',
        'posts_per_page' =>'2',
        'paged'=>$paged
    );
    $my_posts = new WP_Query($args);
    if($my_posts->have_posts())  :
    ?>
    <?php while ($my_posts->have_posts()) :$my_posts->the_post() ?>
    	<li>
    		<div class="thumnail_list">
    			<a href="#">
			        <h2><?php the_title(); ?></h2>
			        <?php the_excerpt(); ?>
			        <?php the_post_thumbnail(); ?>
		        </a>
	    	</div>
		<?php endif; ?>
        </li>
    <?php
    endwhile;
    endif;
    wp_die( );
}

https://ajaxmp.jsajaxmp.js

jQuery(document).ready(function($) {
	$.ajax({
        type : 'POST',
        data : {'action' : 'load_posts_by_ajax', 'page' : 2},
        url : lionelajax.url,
        success : function (resp){
	            var url = lionelajax.url;
				var page = 2;
				$('body').on('click','.loadmore',function() {
					var data = {
						'action':"load_posts_by_ajax",
						'page':page,
						'security':'<?php echo wp_create_nonce( "load_more_posts" );?>'
					}
					$.post(url,data,function(response) {
					$('.contend_manual').append(response);
					page++;
				});
			});
        }
    });
    return false;
});

Ví dụ 5:

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Sử dụng ajax toàn tập</title>
</head>
<body>
		Bước 1: Tạo none & link
		<?php  
			$nonce = wp_create_nonce("my_user_vote_nonce");
		    $link = admin_url('admin-ajax.php?action=my_user_vote&post_id='.$post->ID.'&nonce='.$nonce);
		    echo '<a class="user_vote" data-nonce="' . $nonce . '" data-post_id="' . $post->ID . '" href="' . $link . '">vote ...</a>';	
		?>
	    Bước 2: Gắn vô hook
	    <?php  
		    add_action("wp_ajax_my_user_vote", "my_user_vote");
			add_action("wp_ajax_nopriv_my_user_vote", "my_must_login");
		?>
		Bước 3: Viết hàm tương ứng
		<?php  
			function my_must_login() {
				if ( !wp_verify_nonce( $_REQUEST['nonce'], "my_user_vote_nonce")) {
			      	exit("No naughty business please");
			   }  
			   	echo "You must log in to vote";
			   	die();
			}
		?>
		Chú ý: Ở trong hàm sử dụng die() vì lý do dừng sử lý hook wp_ajax tiếp sau đó bởi lệnh die().
		Mẫu 2: Dùng Ajax dưới dạng $.ajax();
	    <script>
	    	var post_id = 1;
	    	var nonce = wp_create_nonce("my_user_nonce");
	    	$.ajax({
		         type : "post",
		         dataType : "json",
		         url : '<?php echo htmlspecialchars(admin_url('admin-ajax.php'), ENT_QUOTES); ?>',
		         data : {action: "my_user", post_id : post_id, nonce: nonce},
		         success: function(response) {
		            console.log(response);
		         }
		    }) ;
	    </script>
	    <!-- Chúng ta chèn thêm thư viện jQuery  -->
		<h1>Cách 1: Hướng dẫn đầy đủ sử dụng file js bên ngoài</h1>
		<!-- Bước 1 -->
	   	<?php  
	   		add_action('wp_enqueue_scripts', 'pw_load_scripts');
			function pw_load_scripts() {
			    wp_enqueue_script('pw-script', get_template_directory_uri() . '/js/my_js.js');
			     wp_localize_script('pw-script', 'lionelajax', array(
			            'url' => admin_url('admin-ajax.php')
			        )
			    );
			}
			add_action("wp_ajax_dvd_action", "my_user_vote");
			add_action("wp_ajax_nopriv_dvd_action", "my_user_vote");
			function my_user_vote() {
				echo $_POST['data'];
				die();
			}
	   	?>
	   	<!-- Bước 2: Nội dung file  my_js.js-->
	   	<script>
		   	jQuery(document).ready(function($) {
			    $.ajax({
			        type : 'POST',
			        data : {'action' : 'dvd_action', 'data' : 'Dữ liệu được gửi lên sever'},
			        url : lionelajax.url,
			        success : function (resp){
			            console.log(resp);
			        }
			    });
			    return false;
			});
		</script>
		<h1>Cách 2: Hướng dẫn đầy đủ sử dụng file js bên ngoài</h1>
		<!-- Bước 1 -->
		<?php  
			add_action( 'init', 'my_script_enqueuer' );
			function my_script_enqueuer() {
				wp_enqueue_script( 'jquery' );
			   	wp_enqueue_script( 'my_voter_script_obj', get_template_directory_uri().'/js/my_js.js' );
			   	wp_localize_script( 'my_voter_script_obj', 'lionelajax', array( 'url' => admin_url( 'admin-ajax.php' )));        
			}
			add_action("wp_ajax_dvd_action", "my_user_vote");
			add_action("wp_ajax_nopriv_dvd_action", "my_user_vote");
			function my_user_vote() {
				echo $_POST['data'];
				die();
			}
		?>
		<!-- Bước 2: Nội dung file  my_js.js-->
		<script>
			jQuery(document).ready(function($) {
			    $.ajax({
			        type : 'POST',
			        data : {'action' : 'dvd_action', 'data' : 'Dữ liệu được gửi lên sever'},
			        url : lionelajax.url,
			        success : function (resp){
			            console.log(resp);
			        }
			    });
			    return false;
			});
		</script>
</body>
</html>

Ví dụ 6: Votes Post

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Votes Post</title>
</head>
<body>
	<!-- Bước 1: -->
	<?php
		if(!get_post_meta(4004,"votes",true)){
			add_post_meta(4004,"votes",0);
		};
		$votes = get_post_meta(4004, "votes", true);
		$votes = ($votes == "") ? 0 : $votes;
	?>
	This post has <div id='vote_counter'><?php echo $votes ?></div> votes<br>s
	<?php
		$nonce = wp_create_nonce("my_user_vote_nonce");
		$link = admin_url('admin-ajax.php?action=my_user_vote&post_id=4004&nonce='.$nonce);
	echo '<a class="user_vote" data-nonce="' . $nonce . '" data-post_id=4004 href="' . $link . '">vote for this article</a>';			
	?>
	<!-- Bước 2: -->
	<?php  
		add_action("wp_ajax_my_user_vote", "my_user_vote");
		add_action("wp_ajax_nopriv_my_user_vote", "my_must_login");
		function my_user_vote() {
			   if ( !wp_verify_nonce( $_REQUEST['nonce'], "my_user_vote_nonce")) {
			      	exit("No naughty business please");
			   }   
			   $vote_count = get_post_meta($_REQUEST["post_id"], "votes", true);
			   $vote_count = ($vote_count == '') ? 0 : $vote_count;
			   $new_vote_count = $vote_count + 1;
			   $vote = update_post_meta($_REQUEST["post_id"], "votes", $new_vote_count);
			   if($vote === false) {
			      	$result['type'] = "error";
			      	$result['vote_count'] = $vote_count;
			   }
			   else {
			      	$result['type'] = "success";
			      	$result['vote_count'] = $new_vote_count;
			   }
			   if(!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
			      	$result = json_encode($result);
			      	echo $result;
			   }
			   else {
			      	header("Location: ".$_SERVER["HTTP_REFERER"]);
			   }
		   die();
		 
		}
		 
		function my_must_login() {
		   	echo "You must log in to vote";
		   	die();
		}
	?>
</body>
</html>

Ví dụ 6: randon posts

Bước chuẩn bị: Chuẩn bị  nội dung của randon posts
Bước 1: Nạp file supriced.js 
wp_enqueue_script( 'twentyseventeen-g', get_theme_file_uri( '/inc/supriced.js' ), array( 'jquery' ), '1.0', true );
Bước 2: Bạn tạo copy code sau 
<p><a href="#" id="suprised">Lorem</a></p>
<div id="result">
   <?php  
	get_template_part( 'randon');
   ?>
</div>
Chú ý: Bạn có thể sử dụng giống WP_PLUGIN_URL . '/' . dirname(plugin_basename(__FILE__)) . '/jquery.ajax.readmore.js',
để nạp file

randon.php

<?php  
	/*
	Template name: Randon Posts
	*/
?>
<?php
 	query_posts('posts_per_page=3&orderby=rand');
    if(have_posts()) : 
    	while(have_posts()) : the_post();
    		the_excerpt();
    	endwhile; 
    else:
    	echo "Không có bài viết";
    endif;
    wp_reset_query();
?>

https://supriced.jssupriced.js

jQuery(document).ready(function($) {
	$('#suprised').click(function() {
		var url = "http://localhost/success/new4/more-content";
		$("#result").load(url);
		return false;
	});
});

Hướng dẫn của Demon Warlock

https://ajax.jsajax.js

jQuery(document).ready(function($) {
	var url = $('#morepostt').attr('data-hue');
	$('#morepostt').click(function(event) {
		$('#result').load(url);
	});
	return false;
});

index.php

<?php
/**
 * The main template file
 *
 * This is the most generic template file in a WordPress theme
 * and one of the two required files for a theme (the other being style.css).
 * It is used to display a page when nothing more specific matches a query.
 * E.g., it puts together the home page when no home.php file exists.
 *
 * @link https://codex.wordpress.org/Template_Hierarchy
 *
 * @package WordPress
 * @subpackage Twenty_Seventeen
 * @since 1.0
 * @version 1.0
 */

get_header(); ?>

<div class="wrap" style="max-width: 1000px;">
	<?php if ( is_home() && ! is_front_page() ) : ?>
		<header class="page-header">
			<h1 class="page-title"><?php single_post_title(); ?></h1>
		</header>
	<?php else : ?>
	<header class="page-header">
		<h2 class="page-title"><?php _e( 'Posts', 'twentyseventeen' ); ?></h2>
	</header>
	<?php endif; ?>

	<div id="primary" class="content-area">
		<main id="main" class="site-main" role="main">

			<?php get_template_part('randon'); ?>

		</main><!-- #main -->
		<a id="morepostt" href="javascript:void(0)" data-hue='http://localhost/success/new4/more-content'>More Post</a>
		<div id="result"></div>
	</div><!-- #primary -->
</div><!-- .wrap -->

<?php get_footer();

randon.php

<?php  
	/*
		Template Name: More Content
	*/
?>
<?php
 	query_posts('posts_per_page=3&orderby=rand');
	    if(have_posts()) : 
	    	while(have_posts()) : the_post();
	    		the_excerpt();
	    	endwhile; 
	    else:
	    	echo "Không có bài viết";
	    endif;
    wp_reset_query();
?>