实例讲解jquery与json的结合_jquery

<%@ WebHandler Language="C#" Class="jQueryJSON.Handler" %> 
 
using System; 
using System.Data; 
using System.Web; 
using System.Collections; 
using System.Web.Services; 
using System.Web.Services.Protocols; 
using System.Configuration; 
using System.Data.SqlClient; 
using System.Text; 
using System.Xml; 
using NetServ.Net.Json; 
 
namespace jQueryJSON 
{ 
/// 
 
/// $codebehindclassname$ 的摘要说明 
/// 
 
[WebService(Namespace = "http://tempuri.org/json/")] 
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] 
public class Handler : IHttpHandler 
{ 
readonly int PageSize = int.Parse(ConfigurationManager.AppSettings["PageSize"]); 
public void ProcessRequest(HttpContext context) 
{ 
context.Response.ContentType = "text/plain"; 
//不让浏览器缓存 
context.Response.Buffer = true; 
context.Response.ExpiresAbsolute = DateTime.Now.AddDays(-1); 
context.Response.AddHeader("pragma", "no-cache"); 
context.Response.AddHeader("cache-control", ""); 
context.Response.CacheControl = "no-cache"; 
 
string result = ""; 
if (context.Request.Params["getPageCount"] != null) result = GetPageCount(); 
if (context.Request.Params["pageIndex"] != null) 
{ 
string pageindex = context.Request.Params["pageIndex"]; 
//if (context.Cache.Get(pageindex) != null) 
// result = context.Cache.Get(pageindex).ToString(); 
//else 
//{ 
// result = GetPageData(context.Request.Params["pageIndex"]); 
// context.Cache.Add( 
// pageindex, 
// result, 
// null, 
// DateTime.Now.AddMinutes(1), 
// System.Web.Caching.Cache.NoSlidingExpiration, 
// System.Web.Caching.CacheItemPriority.Default, 
// null); 
//} 
result = GetPageData(context.Request.Params["pageIndex"]); 
} 
context.Response.Write(result); 
} 
 
private string GetPageData(string p) 
{ 
int PageIndex = int.Parse(p); 
string sql; 
if (PageIndex == 1) 
sql = "select top " + PageSize.ToString() + " * from Orders order by OrderID desc"; 
else 
sql = "select top " + PageSize.ToString() + " * from Orders where OrderID not in(select top " + ((PageIndex - 1) * PageSize).ToString() + " OrderID from Orders order by OrderID desc) order by OrderID desc"; 
string dbfile = ConfigurationManager.ConnectionStrings["conn"].ToString(); 
SqlConnection conn = new SqlConnection(dbfile); 
SqlDataAdapter da = new SqlDataAdapter(sql, conn); 
DataTable dt = new DataTable("table"); 
da.Fill(dt); 
return DataTableJson(dt); 
 
} 
 
private string GetPageCount() 
{ 
string dbfile = ConfigurationManager.ConnectionStrings["conn"].ToString(); 
SqlConnection conn = new SqlConnection(dbfile); 
SqlCommand cmd = new SqlCommand("select count(*) from Orders", conn); 
conn.Open(); 
int rowcount = Convert.ToInt32(cmd.ExecuteScalar()); 
conn.Close(); 
return ((rowcount + PageSize - 1) / PageSize).ToString(); 
} 
 
private string DataTable2Json(DataTable dt) 
{ 
StringBuilder jsonBuilder = new StringBuilder(); 
jsonBuilder.Append("{\""); 
jsonBuilder.Append(dt.TableName); 
jsonBuilder.Append("\":["); 
for (int i = 0; i < dt.Rows.Count; i++) 
{ 
jsonBuilder.Append("{"); 
for (int j = 0; j < dt.Columns.Count; j++) 
{ 
jsonBuilder.Append("\""); 
jsonBuilder.Append(dt.Columns[j].ColumnName); 
jsonBuilder.Append("\":\""); 
jsonBuilder.Append(dt.Rows[i][j].ToString()); 
jsonBuilder.Append("\","); 
} 
jsonBuilder.Remove(jsonBuilder.Length - 1, 1); 
jsonBuilder.Append("},"); 
} 
jsonBuilder.Remove(jsonBuilder.Length - 1, 1); 
jsonBuilder.Append("]"); 
jsonBuilder.Append("}"); 
return jsonBuilder.ToString(); 
} 
 
private string DataTableJson(DataTable dt) 
{ 
JsonWriter writer = new JsonWriter(); 
JsonObject content = new JsonObject(); 
JsonArray Orders = new JsonArray(); 
JsonObject Order; 
JsonObject OrderItem = new JsonObject(); 
 
for (int i = 0; i < dt.Rows.Count; i++) 
{ 
Order = new JsonObject(); 
for(int j =0;j