jquery+json实现分页效果
son作为一种轻量级的数据交换格式,由于其传输数据格式的方便性，今天偶然想将其应用于分页实现，分页做为web开发一个长久的话题，其应用的高效与重要性就不多说了
本文主要技术:反射机制，Json数据格式，jquery
为了应用的通用性，首先要根据反射机制，能将要返回的任意类型的结果对象转化成Json类型的格式。
public static String toJSON(Object obj) {HashMap map = new HashMap();
Class c = obj.getClass();// 利用反射机 制，把里面所有的属性，反射出来使用，这样放入任何一个对象， 都可以找到他们的属性，// 把这些属性的名，和属性的值，封装成一个map里，Field[] fields = c.getDeclaredFields();for (int i = 0; i < fields.length; i++) {
String name = fields[i].getName();try {
fields[i].setAccessible(true);
Object o = fields[i].get(obj);i f (o instanceof Number) {
map.put(""" + name + """, o.toString());
} else if (o instanceof String) {
map.put(""" + name + """, """ + o.toString() + """);
}} catch (IllegalArgumentException e) {
} catch (IllegalAccessException e) {
}}/ / 把map对象变成字符串// 这些格式还需要把=变成:String s = map.toString();/ /System.out.println(s);String str = s.replaceAll(""=", "":");
//System.out.println(str);return str;
}将要返回的多个对象转换成Json类型的对象后，最后应加上分页的信息，最终将多个Json字符串，转化成一整个Json类型
{"0":{"id":"0", "name":"dong0", "age":21},
"1":{"id":"1", "name":"dong1", "age":21},
"2":{"id":"2", "name":"dong2", "age":21},
"3":{"id":"3", "name":"dong3", "age":21},
"4":{"id":"4", "name":"dong4", "age":21},
"5":{"id":"5", "name":"dong5", "age":21},
"6":{"id":"6", "name":"dong6", "age":21},
"7":{"id":"7", "name":"dong7", "age":21},
"8":{"id":"8", "name":"dong8", "age":21},
"9":{"id":"9", "name":"dong9", "age":21},
"10":{"firstPage":1, "currentPage":1,
"default_Record_Num":10, "lastPage":10, "frontPage":1, "sum":100, "nextPage":2},
"length":11}
当信息发送到客户端时 ，只用jquery接收对象的数据就行了 ，这样 可以实现前台的样式与后台传送的数据分离，更加简化了代码
$.getJSON("result.jsp?page="+p, function(json)
{$("#show").html("<tr><th>用户ID</th><th>用户名</th><th>用户年龄</th></tr>");
for(var i=0 ; i<json.length-1; i++){
$("#show").append("<tr><td>"+json[i]["id"]+"</td><td>"+json[i]["name"]+"</ td><td>"
+json[i]["age"]+"</td></tr>");
}$("#currentPage").attr("value",json[json.length-1]["currentPage"]);
$("#pageCount").attr("value",json[json.length-1]["lastPage"]);
});利用JQuery与JSon实现的无刷新分页代码，具体代码如下
需要四个文件
一个实体类文件 CategoryInfoModel.cs
一个SqlHelper SQLHelper.cs
一个AJAX服务端处理程序 PagedService.ashx
一个客户端调用页面 WSXFY.htm
CategoryInfoModel.cs和SQLHelper.cs我就不写了，都知道是什么文件
PagedService.ashx 代码如下
using System.Web.Script.Serialization; public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; string strAction = context.Request["Action"]; //取页数 if (strAction == "GetPageCount") { string strSQL = "SELECT COUNT(*) FROM CategoryInfo"; int intRecordCount = SqlHelper.ExecuteScalar(strSQL); int intPageCount = intRecordCount / 10; if (intRecordCount % 10 != 0) { intPageCount++; } context.Response.Write(intPageCount); }//取每页数据 else if (strAction == "GetPageData") { string strPageNum = context.Request["PageNum"]; int intPageNum = Convert.ToInt32(strPageNum); int intStartRowIndex = (intPageNum - 1) * 10 + 1; int intEndRowIndex = (intPageNum) * 10 + 1; string strSQL = "SELECT * FROM ( SELECT ID,CategoryName,Row_Number() OVER(ORDER BY ID ASC) AS rownum FROM CategoryInfo) AS t"; strSQL += " WHERE t.rownum >= " + intStartRowIndex + " AND t.rownum <= " + intEndRowIndex; DataSet ds = new DataSet(); SqlConnection conn = SqlHelper.GetConnection(); ds = SqlHelper.ExecuteDataset(conn, CommandType.Text, strSQL); List<CategoryInfoModel> categoryinfo_list = new List<CategoryInfoModel>();//定义实体集合
for (int i = 0; i < ds.Tables[0].Rows.Count; i++) { CategoryInfoModel categoryinfo = new CategoryInfoModel(); categoryinfo.CategoryInfoID = Convert.ToInt32(ds.Tables[0].Rows[i]["ID"]); categoryinfo.CategoryName = ds.Tables[0].Rows[i]["CategoryName"].ToString(); categoryinfo_list.Add(categoryinfo); } JavaScriptSerializer jss = new JavaScriptSerializer(); context.Response.Write(jss.Serialize(categoryinfo_list));//序列化实体集合为javascript对象 } } WSXFY.htm 代码如下
<head>
<title>无刷新分页</title>
<script type="text/javascript" src="../Scripts/jquery-1.5.1.min.js"></script>
<script type="text/javascript">
$(function () { $.post("PagedService.ashx", { "Action": "GetPageCount" }, function (response, status) { for (var i = 1; i <= response; i++) { var td = $("<td><a href=\'\'>" + i + "</a></td>");
$("#trPage").append(td); td.click(function (e) { e.preventDefault(); //不要导向链接 $.post("PagedService.ashx", { "Action": "GetPageData", "PageNum":$(this).text() }, function (response, status) { var categorys = $.parseJSON(response); $("#ulCategory").empty(); for (var i = 0; i < categorys.length; i++) {
var category = categorys[i];
var li = $("<li>" + category.CategoryInfoID + "-" + category.CategoryName + "</li>");
$("#ulCategory").append(li); } }); }); } }); }); </script>
</head>
<body>
<ul id="ulCategory"></ul>
<table>
<tr id="trPage">
</tr>
</table>
</body>
</html>