从数据库加载更多项目 ~ 无限滚动

我是ajax/php的新手，所以我试图找出最好的方法。

我有一个包含 1500 个项目的 sql 数据库填充，我正在加载到我的页面中。我想将 30 个项目加载到页面中，然后当用户到达网页底部时，我希望它再加载 30 个项目。

到目前为止，我的网页上显示了 30 个项目，并带有一个过滤项目的下拉菜单。我还有一个函数，当用户到达页面底部时触发。

谁能帮我使用 PHP 脚本来完成这项工作并加载更多项目？我使用的代码如下。

谢谢

.HTML

<section id="filters">
    <select name="entries"  onchange="filterEntries()">
        <option value="*">show all</option>
        <option value=".item323">323</option>
        <option value=".item266">266</option>
        <option value=".item277">277</option>
        <option value=".item289">289</option>
    </select>
</section> <!-- #filters -->
<div id="entries" class="clearfix">
    <div class="ajaxloader"><img src="<?php bloginfo('template_url'); ?>/ajax_load.gif" alt="loading..." /></div><!--ajaxloader-->
</div><!--entries-->
<div class="ajaxloader"><img src="<?php bloginfo('template_url'); ?>/ajax_load.gif" alt="loading..." /></div><!--ajaxloader-->

Jquery

$(document).ready(function () {
    loadData();
    //Hide Loader for Infinite Scroll
    $('div.ajaxloader').hide();
});
function loadData () {
//Show Loader for main content
    $('#entries .ajaxloader').show();
//Pull in data from database
if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari
        "use strict";
        xmlhttp=new XMLHttpRequest(); 
    }
    else {// code for IE6, IE5
        xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
    xmlhttp.onreadystatechange=function() {
        if (xmlhttp.readyState===4 && xmlhttp.status===200) {    
        document.getElementById("entries").innerHTML=xmlhttp.responseText;
        //Fire filter function once data loaded
            filterEntries();
            //Hide Loader for main content once loaded
            $('#entries .ajaxloader').hide();
    }
    }
    xmlhttp.open("POST","<?php bloginfo('template_url'); ?>/getentries.php?$number",true);
    xmlhttp.send();
};

//Isotope filter
function filterEntries () {
    var $container = $('#entries');
       $select = $('#filters select');
    $container.isotope({
        itemSelector : '.item'
    });
    $select.change(function() {
    var filters = $(this).val();
    $container.isotope({
            filter: filters
    });
});
};
$(window).scroll(function () {
    if ($(window).scrollTop() >= $(document).height() - $(window).height() - 10) {
    $('div.ajaxloader').show('slow');
        //alert("Function to load more entries");
    }
});

.PHP

<?php
    //Connect to Database
    $con = mysql_connect("localhost", "root", "root");
    if (!$con) {
        die('Could not connect: ' . mysql_error());
    }
    mysql_select_db("awards", $con);

    $sql="SELECT * FROM entry WHERE  status = 'registered' ORDER BY `entry_id` LIMIT 0, 30";
    $result = mysql_query($sql);

    while($row = mysql_fetch_array($result)) {
        //Get award cat ids
        $awardcat =  $row['awards_subcategory_id']  ;
        print "<div class='item item$awardcat clearfix'>";//add award cat id to each div
        print '<img class="image" src="http://localhost:8888/awardsite/wp-content/themes/award/placeholder.jpg" />';
        print "<p > Studio: " . $row['studio'] . "</p>";
        print "<p class='client'> Client: " . $row['client'] . "</p>";
        print "<p class='description'> Description: " . $row['description'] . "</p>";
        print "<p class='solutionprocess'> Solution Process: " . $row['solution_process'] . "</p>";
        print "</div>";
    }


    mysql_close($con);
?> 

$(document).ready(function () {
    loadData( 0 );
    //Hide Loader for Infinite Scroll
    $('div.ajaxloader').hide();
});
function loadData ( last_id ) {
    var $entries = $('#entries'),
        $loader = $('.ajaxloader', $entries).show();
    $.get( '/getentries.php', { last_id : last_id }, function( data ) {
        $entries.append( data ).append( $loader.hide() );
        filterEntries();
    });
};

//Isotope filter - no changes to this code so I didn't include it
$(window).scroll(function () {
    if ($(window).scrollTop() >= $(document).height() - $(window).height() - 10) {
        $('div.ajaxloader').show('slow');
        loadData( $( '#entries item:last' ).data('id') )
    }
});

<?php
//Connect to Database
$con = new mysqli( 'localhost', 'root', 'root', 'awards' );
if( $con->connect_errno ) {
    die( 'Could not connect:' . $con->connect_error );
}
$last_id = isset( $_GET['last_id'] ) ? (int)$_GET['last_id'] : 0; 
$stmt = $con->prepare( 'SELECT * FROM entry WHERE status = "registered" AND entry_id > (?) ORDER BY entry_id LIMIT 0, 30' );
$stmt->bind_param( 'i', $last_id );
$stmt->execute();
$result = $stmt->get_result();    
while( $row = $result->fetch_assoc() ) {
    //Get award cat ids
    $awardcat = $row['awards_subcategory_id'];
    print "<div class='item item$awardcat clearfix' data-id='" . $row['entry_id'] . "'>";//add award cat id to each div
    print '<img class="image" src="http://localhost:8888/awardsite/wp-content/themes/award/placeholder.jpg" />';
    print "<p > Studio: " . $row['studio'] . "</p>";
    print "<p class='client'> Client: " . $row['client'] . "</p>";
    print "<p class='description'> Description: " . $row['description'] . "</p>";
    print "<p class='solutionprocess'> Solution Process: " . $row['solution_process'] . "</p>";
    print "</div>";
}
$con->close();