例子和<<Ajax基礎教程>>中的那個例子類似，不過書中的例子是用java寫的server端code，我這裏用.net再寫一次：
我就直接把客戶端的code帖出來了：
<!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>無標題頁</title> <script type="text/javascript" src="json.js"></script>
<script type="text/javascript">
var xmlHttp;function createXMLHttpRequest() 
{
if (window.ActiveXObject) { xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
} else if (window.XMLHttpRequest) { xmlHttp = new XMLHttpRequest(); }} function doJSON(){ createXMLHttpRequest(); var car=getCarObject(); //alert("Car object as JSON: "+car.toJSONString()); xmlHttp.onreadystatechange=handleStateChange; xmlHttp.open("post","dojson.aspx",true); xmlHttp.setRequestHeader("content-type","application/x-www-form-urlencode"); xmlHttp.send(car.toJSONString());}function getCarObject(){ return new Car("Dodge","Coronet R/T",1968,"yellow"); }function Car(make,model,year,color){ this.Make=make; this.Model=model; this.Year=year; this.Color=color;} function handleStateChange() { if(xmlHttp.readyState == 4) { if(xmlHttp.status == 200) { parseResults(); } }}function parseResults() { var responseDiv = document.getElementById("serverResponse"); if(responseDiv.hasChildNodes()) { responseDiv.removeChild(responseDiv.childNodes[0]); } var responseText = document.createTextNode(xmlHttp.responseText); responseDiv.appendChild(responseText);}
</script></head><body> <br /> <br /> <form action="#"> <input type="button" value="Click here to send JSON data to the server" onclick="doJSON();" /> </form> <h2> Server Response:</h2> <div id="serverResponse"> </div></body></html>這上面ajax的部分就不再詳解了.
重點在server端：
我在這裏實現和原書中同樣的目的，同樣帖出全部的code:
using System;using System.Data;using System.Configuration;using System.Collections;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using System.IO;using Newtonsoft.Json;using Newtonsoft.Json.Converters;public partial class dojson : System.Web.UI.Page{ protected void Page_Load(object sender, EventArgs e) { byte[] b = new byte[this.Request.InputStream.Length]; this.Request.InputStream.Read(b, 0, b.Length); string s = System.Text.Encoding.Default.GetString(b); Car car = (Car)JavaScriptConvert.DeserializeObject(s, typeof(Car)); string str = ""; str = "You have a " + car.Year + " " + car.Make + " " + car.Model + " that is " + car.Color + " in color."; this.Response.Write(str); this.Response.Flush(); this.Response.Close(); } private class Car { public Car() { } private string make; public string Make { get { return make; } set { make = value; } } private string model; public string Model { get { return model; } set { model = value; } } private int year; public int Year { get { return year; } set { year = value; } } private string color; public string Color { get { return color; } set { color = value; } } }}
這裏用了最近的Newtonsoft.Json.dll，是2007-3-20的，也就是Json.NET 1.2版，詳見http://www.newtonsoft.com/blog/
主要用了一個反序列化，JavaScriptConvert.DeserializeObject，對在javascript中的object另外在C#裏定義一個class,利用JavaScriptConvert.DeserializeObject方法做反序列化，可以從json的字符串裏得到Car的一個實例，這樣就可以完成下面的工作了．