jQuery+.net实现浏览更多内容(改编php版本)
改编自php版本,原文:
jQuery+PHP实现浏览更多内容http://www.helloweba.com/view-blog-130.html
这里记录.net 下的实现
一、首先创建数据库表test,并插入一些测试数据:
代码如下:
go
if exists (select * from sysobjects where name='test')
drop table [test]
go
CREATE TABLE [test](
[id] [int] IDENTITY(1,1),
[author] [varchar](50),
[content] [varchar](2000),
[createOn] [datetime]
)
declare @index int;
set @index = 1;
while(@index < 1000)
begin
insert into test([author],[content],[createOn])
values
('author' + cast(@index as varchar(4)),'content' + cast(@index as varchar(4)),DATEADD(DAY,@index,getdate()))
set @index = @index + 1
end
go
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<script src="js/jquery-1.4.4.min.js" type="text/javascript"></script>
<script src="js/jquery.more.js" type="text/javascript"></script>
<script type="text/javascript">
$(function () {
$('#more').more({ 'address': 'ajax/data.ashx' }) //这里为向后台请求地址
});
</script>
<style type="text/css">
more
{
margin: 10px auto;
width: 560px;
border: 1px solid #999;
}
.single_item
{
padding: 20px;
border-bottom: 1px dotted #d3d3d3;
}
.author
{
position: absolute;
left: 0px;
font-weight: bold;
color: #39f;
}
.createOn
{
position: absolute;
right: 0px;
color: #999;
}
.content
{
line-height: 20px;
word-break: break-all;
}
.element_head
{
width: 100%;
position: relative;
height: 20px;
}
.get_more
{
margin: 10px;
text-align: center;
}
.more_loader_spinner
{
width: 20px;
height: 20px;
margin: 10px auto;
background: url(loader.gif) no-repeat;
}
</style>
</head>
<body>
<div id="more">
<div class="single_item">
<div class="element_head">
<div class="createOn">
</div>
<div class="author">
</div>
</div>
<div class="content">
</div>
</div>
<a href="javascript:;" class="get_more">::点击加载更多内容::</a>
</div>
</body>
</html>
<%@ WebHandler Language="C#" Class="data" %>
using System;
using System.Web;
using Microsoft.Practices.EnterpriseLibrary.Data;
public class data : IHttpHandler {
public void ProcessRequest (HttpContext context) {
context.Response.ContentType = "text/plain";
int last = Convert.ToInt32(context.Request.Params["last"]); //开始记录数
int amount = Convert.ToInt32(context.Request.Params["amount"]); //单次显示记录数
Database db = DatabaseFactory.CreateDatabase();
////这里日期字段createOn先格式一下,否则会生成类似这种格式/Date(1310292162507)/
string sql = string.Format("select id,author,content,convert(varchar(100), createOn, 120) createOn from ( select row_number() over (order by id) as rowNum,* from test) as t "
+ " where rowNum>{0} and rowNum<={1}", last, last + amount);
System.Data.DataTable dt = db.ExecuteDataSet(System.Data.CommandType.Text,sql).Tables[0];
context.Response.Write(JSONHelper.DataTableToJSON(dt)); //输出json格式
}
public bool IsReusable {
get {
return false;
}
}
}
(function( $ ){
var target = null;
var template = null;
var lock = false;
var variables = {
'last' : 0
}
var settings = {
'amount' : '10',
'address' : '',
'format' : 'json',
'template' : '.single_item',
'trigger' : '.get_more',
'scroll' : 'false',
'offset' : '100',
'spinner_code': ''
}
var methods = {
init : function(options){
return this.each(function(){
if(options){
$.extend(settings, options);
}
template = $(this).children(settings.template).wrap('<div/>').parent();
template.css('display','none')
$(this).append('<div class="more_loader_spinner">'+settings.spinner_code+'</div>')
$(this).children(settings.template).remove()
target = $(this);
if(settings.scroll == 'false'){
$(this).find(settings.trigger).bind('click.more',methods.get_data);
$(this).more('get_data');
}
else{
if($(this).height() <= $(this).attr('scrollHeight')){
target.more('get_data',settings.amount*2);
}
$(this).bind('scroll.more',methods.check_scroll);
}
})
},
check_scroll : function(){
if((target.scrollTop()+target.height()+parseInt(settings.offset)) >= target.attr('scrollHeight') && lock == false){
target.more('get_data');
}
},
debug : function(){
var debug_string = '';
$.each(variables, function(k,v){
debug_string += k+' : '+v+'\n';
})
alert(debug_string);
},
remove : function(){
target.children(settings.trigger).unbind('.more');
target.unbind('.more')
target.children(settings.trigger).remove();
},
add_elements : function(data){
//alert('adding elements')
var root = target
// alert(root.attr('id'))
var counter = 0;
if(data){
$(data).each(function(){
counter++
var t = template
$.each(this, function(key, value){
if(t.find('.'+key)) t.find('.'+key).text(value);
})
//t.attr('id', 'more_element_'+ (variables.last++))
if(settings.scroll == 'true'){
// root.append(t.html())
root.children('.more_loader_spinner').before(t.html())
}else{
// alert('...')
root.children(settings.trigger).before(t.html())
}
root.children(settings.template+':last').attr('id', 'more_element_'+ ((variables.last++)+1))
})
}
else methods.remove()
target.children('.more_loader_spinner').css('display','none');
if(counter < settings.amount) methods.remove()
},
get_data : function(){
// alert('getting data')
var ile;
lock = true;
target.children(".more_loader_spinner").css('display','block');
$(settings.trigger).css('display','none');
if(typeof(arguments[0]) == 'number') ile=arguments[0];
else {
ile = settings.amount;
}
$.post(settings.address, {
last : variables.last,
amount : ile
}, function(data){
$(settings.trigger).css('display','block')
methods.add_elements(data)
lock = false;
}, settings.format)
}
};
$.fn.more = function(method){
if(methods[method])
return methods[ method ].apply( this, Array.prototype.slice.call( arguments, 1 ));
else if(typeof method == 'object' || !method)
return methods.init.apply(this, arguments);
else $.error('Method ' + method +' does not exist!');
}
})(jQuery)