緊接著上篇—分頁技術原理與實現之Java+Oracle代碼實現分頁(二) ，本篇繼續分析分頁技術。上篇講的是分頁技術的代碼實現，這篇繼續分析一下分頁技術的效果控制。
上篇已經用代碼簡單的實現了一個分頁。但是我們都看到，代碼中每次通過servlet請求取得結果集後，都會轉向到一個jsp頁面顯示結果，這樣每次查詢頁面都會刷新一下，比如查詢出現結果集後要查看第三頁，頁面就會刷新一下。這樣頁面給人的效果感覺就會有點不舒服，所以我們希望能夠在通過條件查詢結果集後無論訪問哪一頁，頁面都不會刷新，而只是結果集變化。要解決這個，我想大家很容易就會想到Ajax了。
是啊，這就要請Ajax出山了。當通過查詢條件查詢到結果集後，以後每次訪問任何一頁都通過Ajax來訪問，使用異步Ajax與Servlet進行交互，將結果查詢出來返回給Ajax，這樣頁面內容因為Ajax返回結果而改變，而頁面卻不會刷新，這就實現了無刷新的分頁技術。
下面我們來看一個簡單的無刷新分頁實現，代碼如下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<link rel="stylesheet" href="../lib/jquery_pagination/pagination.css" mce_href="lib/jquery_pagination/pagination.css" />
<mce:script type="text/<a href="http://lib.csdn.net/base/javascript" class='replace_word' title="JavaScript知識庫" target='_blank' style='color:#df3434; font-weight:bold;'>JavaScript</a>" src="../lib/<a href="http://lib.csdn.net/base/jquery" class='replace_word' title="jQuery知識庫" target='_blank' style='color:#df3434; font-weight:bold;'>jQuery</a>/jquery.min.js" mce_src="lib/jquery/jquery.min.js"></mce:script>
<mce:script type="text/javascript"
src="../lib/jquery_pagination/jquery.pagination.js"></mce:script>
<mce:script type="text/javascript"><!--
/**
* Callback function that displays the content.
*
* Gets called every time the user clicks on a pagination link.
*
* @param {int}page_index New Page index
* @param {jQuery} jq the <a href="http://lib.csdn.net/base/docker" class='replace_word' title="Docker知識庫" target='_blank' style='color:#df3434; font-weight:bold;'>Container</a> with the pagination links as a jQuery object
*/
function pageselectCallback(page_index, jq) {
var new_content = $('#hiddenresult div.result:eq(' + page_index + ')')
.clone();
$('#Searchresult').empty().append(new_content);
return false;
}
function initPagination() {
var num_entries = $('#hiddenresult div.result').length;
// Create pagination element
$("#Pagination").pagination(num_entries, {
num_edge_entries : 2,
num_display_entries : 8,
callback : pageselectCallback,
items_per_page : 1
});
}
// When the HTML has loaded, call initPagination to paginate the elements
$(document).ready(function() {
initPagination();
});
// --></mce:script>
<mce:style type="text/css"><!--
* {
padding: 0;
margin: 0;
}
body {
background-color: #fff;
margin: 20px;
padding: 0;
height: 100%;
font-family: Arial, Helvetica, sans-serif;
}
#Searchresult {
margin-top: 15px;
margin-bottom: 15px;
border: solid 1px #eef;
padding: 5px;
background: #eef;
width: 40%;
}
#Searchresult p {
margin-bottom: 1.4em;
}
--></mce:style><style type="text/css" mce_bogus="1">* {
padding: 0;
margin: 0;
}
body {
background-color: #fff;
margin: 20px;
padding: 0;
height: 100%;
font-family: Arial, Helvetica, sans-serif;
}
#Searchresult {
margin-top: 15px;
margin-bottom: 15px;
border: solid 1px #eef;
padding: 5px;
background: #eef;
width: 40%;
}
#Searchresult p {
margin-bottom: 1.4em;
}</style>
<title>Pagination</title>
</head>
<body>
<h4>
jQuery Pagination Plugin Demo
</h4>
<div id="Pagination" class="pagination">
</div>
<br style="clear: both;" mce_style="clear: both;" />
<div id="Searchresult">
This content will be replaced when pagination inits.
</div>
<div id="hiddenresult" style="display: none;" mce_style="display: none;">
<div class="result">
<p>
Globally maximize granular "outside the box" thinking vis-a-vis
quality niches. Proactively formulate 24/7 results whereas 2.0
catalysts for change. Professionally implement 24/365 niches rather
than client-focused users.
</p>
<p>
Competently engineer high-payoff "outside the box" thinking through
cross functional benefits. Proactively transition intermandated
processes through open-source niches. Progressively engage
maintainable innovation and extensible interfaces.
</p>
</div>
<div class="result">
<p>
Credibly fabricate e-business models for end-to-end niches.
Compellingly disseminate integrated e-markets without ubiquitous
services. Credibly create equity invested channels with
multidisciplinary human capital.
</p>
<p>
Interactively integrate competitive users rather than fully tested
infomediaries. Seamlessly initiate premium functionalities rather
than impactful architectures. Rapidiously leverage existing
resource-leveling processes via user-centric portals.
</p>
</div>
<div class="result">
<p>
Monotonectally initiate unique e-services vis-a-vis client-centric
deliverables. Quickly impact parallel opportunities with B2B
bandwidth. Synergistically streamline client-focused
infrastructures rather than B2C e-commerce.
</p>
<p>
Phosfluorescently fabricate 24/365 e-business through 24/365 total
linkage. Completely facilitate high-quality systems without
stand-alone strategic theme areas.
</p>
</div>
</div>
</body>
</html>
這就是一個非常簡單的無刷新分頁實現，使用了JQuery+ jquery.pagination框架。現在隨著框架的流行，尤其是Jquery的流行，使用框架來開發是非常有效的。上面代碼原理在代碼中已有注釋，也可參考Jquery的官方網站：。
現在就可以來開發我們的Ajax無刷新分頁實現。基於上面的原理，在響應頁碼被按下的代碼中pageselectCallback()，我們使用一個Ajax異步訪問數據庫，通過點擊的頁號將結果集取出後再用異步設置到頁面，這樣就可以完成了無刷新實現。
頁碼被按下的響應函數pageselectCallback()修改如下：
這樣就可以用異步方式獲取結果，用showResponse函數來處理結果了，showResponse函數如下：
function showResponse(request){
var content = request;
var root = content.documentElement;
var responseNodes = root.getElementsByTagName("root");
var itemList = new Array();
var pageList=new Array();
alert(responseNodes.length);
if (responseNodes.length > 0) {
var responseNode = responseNodes[0];
var itemNodes = responseNode.getElementsByTagName("data");
for (var i=0; i<itemNodes.length; i++) {
var idNodes = itemNodes[i].getElementsByTagName("id");
var nameNodes = itemNodes[i].getElementsByTagName("name");
var sexNodes=itemNodes[i].getElementsByTagName("sex");
var ageNodes=itemNodes[i].getElementsByTagName("age");
if (idNodes.length > 0 && nameNodes.length > 0&&sexNodes.length > 0&& ageNodes.length > 0) {
var id=idNodes[0].firstChild.nodeValue;
var name = nameNodes[0].firstChild.nodeValue;
var sex = sexNodes[0].firstChild.nodeValue;
var age=ageNodes[0].firstChild.nodeValue;
itemList.push(new Array(id,name, sex,age));
}
}
var pageNodes = responseNode.getElementsByTagName("pagination");
if (pageNodes.length>0) {
var totalNodes = pageNodes[0].getElementsByTagName("total");
var startNodes = pageNodes[0].getElementsByTagName("start");
var endNodes=pageNodes[0].getElementsByTagName("end");
var currentNodes=pageNodes[0].getElementsByTagName("pageno");
if (totalNodes.length > 0 && startNodes.length > 0&&endNodes.length > 0) {
var total=totalNodes[0].firstChild.nodeValue;
var start = startNodes[0].firstChild.nodeValue;
var end = endNodes[0].firstChild.nodeValue;
var current=currentNodes[0].firstChild.nodeValue;
pageList.push(new Array(total,start,end,current));
}
}
}
showTable(itemList,pageList);
}
如上代碼就是用來處理通過Ajax異步請求Servlet後返回的XML格式的結果，其中Servlet代碼在上篇中。其中itemList、pageList分別是解析返回後生成的用戶List和分頁導航，這樣用戶就可以以自己的展現方式展現數據了。
function pageselectCallback(page_index, jq){
var pars="pageNo="+(page_index+1);
$.ajax({
type: "POST",
url: " UserBasicSearchServlet",
cache: false,
data: pars,
success: showResponse
});
return false;
}
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持。