asp.net点击 查看更多 实现无刷新加载的实现代码

<script type="text/javascript">
$(function () {
function init(count, start) {
$.ajax({
type: "GET",
dataType: "json",
url: "Handler/Handler.ashx",
data: { action: "GetMoreNews", count: count, start: start },
beforeSend: function () { $("#divload").show(); $("#more2").hide(); },
complete: function () { $("#divload").hide(); $("#more2").show(); },
success: function (json) {
var str = "";
$.each(json, function (index, array) {
var str = "<div class='single_item'>"
+ "<div class='element_head'>"
+ "<div class='author'>" + array['Title'] +"</div>"
+ "<div class='date'>" + array['Date'] + "</div>"
+ "</div>"
+ "<div class='content'>" + array['Contents'] + "</div>"
+ "</div>";
$("#more").append(str);
});
if (json == "") {
$("#more2").html("没有更多内容加载了……");
}
}
});
}
var count = 5;
var start = 0;
init(count, start);
$(".get_more").click(function () {
start += 5;
init(count, start);
});
});
</script>

页面页面的js代码如下，
<b> <script type="text/javascript">
$(function () {
function init(count, start) {
$.ajax({
type: "GET",
dataType: "json",
url: "Handler/Handler.ashx",
data: { action: "GetMoreNews", count: count, start: start },
beforeSend: function () { $("#divload").show(); $("#more2").hide(); },
complete: function () { $("#divload").hide(); $("#more2").show(); },
success: function (json) {
var str = "";
$.each(json, function (index, array) {
var str = "<div class='single_item'>"
+ "<div class='element_head'>"
+ "<div class='author'>" + array['Title'] +"</div>"
+ "<div class='date'>" + array['Date'] + "</div>"
+ "</div>"
+ "<div class='content'>" + array['Contents'] + "</div>"
+ "</div>";
$("#more").append(str);
});
if (json == "") {
$("#more2").html("没有更多内容加载了……");
}
}
});
}
var count = 5;
var start = 0;
init(count, start);
$(".get_more").click(function () {
start += 5;
init(count, start);
});
});
</script></b>
解释上面js的大体意思：定义一个init方法，此方法带有两个参数count和start，count意思是每次加载显示评论数，start意思是，每次从数据库中读取的位置，比如0，5,10。
Handler.ashx处理页面的代码如下
[code]
case "GetMoreNews":
int count = int.Parse(context.Request.QueryString["count"].ToString());
int start = int.Parse(context.Request.QueryString["start"].ToString());
IList<WineNews> morenews = WineNewsManager.WineNewsQueryFromMToN(count,start);
Content = JavaScriptConvert.SerializeObject(morenews);
break;

public static IList<WineNews> WineNewsQueryFromMToN(int count,int start)
{
using (SqlConnection cn = new SqlConnection(SQLHelp.Conn))
{
cn.Open();
string sql = "SELECT TOP " + count + " f.* FROM tb_WineNews f WHERE Id NOT IN (SELECT TOP " + start + " Id FROM tb_WineNews ORDER BY Id desc) ORDER BY Id desc";
SqlCommand cmd = new SqlCommand(sql, cn);
SqlDataReader dr = cmd.ExecuteReader();
IList<WineNews> list = new List<WineNews>();
while (dr.Read())
{
WineNews wineNews = new WineNews();
if (dr["ID"] != DBNull.Value)
{
wineNews.ID = (int)dr["ID"];
}
if (dr["Title"] != DBNull.Value)
{
wineNews.Title = (string)dr["Title"];
}
if (dr["Contents"] != DBNull.Value)
{
wineNews.Contents = (string)dr["Contents"];
}
if (dr["Picture"] != DBNull.Value)
{
wineNews.Picture = (string)dr["Picture"];
}
if (dr["Date"] != DBNull.Value)
{
wineNews.Date = ((DateTime)dr["Date"]).ToString("yyyy-MM-dd HH:mm:ss");
}
list.Add(wineNews);
}
dr.Close();
return list;
}
}