如何读取JSON

采用第三方组件
Jayrock 和 Jayrock.Json首先引入命名空间
using Jayrock.Json;其次，创建 JsonObject 对象，步骤如下：string strJsonText = @"{"cacheCount":1,"count":"34","slice":"5, 5","list":[1001598,1001601,1001605,1001609,1001612],"page":1,"error":200}";JsonReader reader = new JsonTextReader(new StringReader(strJsonText));JsonObject jsonObj = new JsonObject();
jsonObj.Import(reader);这样，就将一个文本的JSon数据转变成一个对象，如果要获取 count 的值，则可以这样string count = jsonObj["count"].ToString();但是有个问题，list 是一个数组，该如何获取呢？不用急，Jayrock已经为我们准备好了，来看using (JsonTextReader textReader = new JsonTextReader(new StringReader(jsonObj["list"].ToString())))
{
                    while (textReader.Read())
                    {
                        if (!string.IsNullOrEmpty(textReader.Text))
                        {
                            Response.Write(textReader.Text);
                        }
                    }
}将数组的内容再赋予一个JsonTextReader对象 ,利用其Read方法进行逐行读取就OK了当然，你也可以使用 JsonArray 对象，这里就不再叙述了

可以用ajax读取Json数据，或者在EXTJS中读取的json数据

直接JS
加eval（）转换就就可以了JS要好好学习的啊

用Ajax读取JSON格式的数据，也需要先用XMLHttpRequest对象的responseText属性读取，然后再用Function构造返回JSON对象的方法，能过方法创建JSON对象。代码如下：
1、Client - helloworld.htm
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
     "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>Ajax Hello World</title>
<script type="text/javascript">
var xmlHttp;function createXMLHttpRequest(){
     if(window.ActiveXObject){
         xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
     }
     else if(window.XMLHttpRequest){'
         xmlHttp = new XMLHttpRequest();
     }
}
function startRequest(){
     createXMLHttpRequest();:
     try{
         xmlHttp.onreadystatechange = handleStateChange;
         xmlHttp.open("GET", "data.txt", true);
         xmlHttp.send(null);
     }catch(exception){
         alert("您要访问的资源不存在!");
     }
}
function handleStateChange(){
     if(xmlHttp.readyState == 4){
         if (xmlHttp.status == 200 || xmlHttp.status == 0){
             // 取得返回字符串
             var resp = xmlHttp.responseText;
             // 构造返回JSON对象的方法
             var func = new Function("return "+resp);
             // 得到JSON对象
             var json = func( );
             // 显示返回结果- \+
             alert("JSON's value: " + json.info + "(" + json.version + "v)");
         };
     })
}/
</script>
</head>
<body>
    <div>
        <input type="button" value="return ajax JSON's value"+
                 onclick="startRequest();" />
</div>
</body>.
</html>
2、Server - data.txt{: a
info: "hello world!",
    version: "2.0"
}

用Ajax读取JSON格式的数据，也需要先用XMLHttpRequest对象的responseText属性读取，然后再用Function构造返回JSON对象的方法，能过方法创建JSON对象。代码如下：
1、Client - helloworld.htm
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
     "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>Ajax Hello World</title>
<script type="text/javascript">
var xmlHttp;function createXMLHttpRequest(){
     if(window.ActiveXObject){
         xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
     }
     else if(window.XMLHttpRequest){'
         xmlHttp = new XMLHttpRequest();
     }
}
function startRequest(){
     createXMLHttpRequest();:
     try{
         xmlHttp.onreadystatechange = handleStateChange;
         xmlHttp.open("GET", "data.txt", true);
         xmlHttp.send(null);
     }catch(exception){
         alert("您要访问的资源不存在!");
     }
}
function handleStateChange(){
     if(xmlHttp.readyState == 4){
         if (xmlHttp.status == 200 || xmlHttp.status == 0){
             // 取得返回字符串
             var resp = xmlHttp.responseText;
             // 构造返回JSON对象的方法
             var func = new Function("return "+resp);
             // 得到JSON对象
             var json = func( );
             // 显示返回结果- \+
             alert("JSON's value: " + json.info + "(" + json.version + "v)");
         };
     })
}/
</script>
</head>
<body>
    <div>
        <input type="button" value="return ajax JSON's value"+
                 onclick="startRequest();" />
</div>
</body>.
</html>
2、Server - data.txt
{
info: "hello world!",
    version: "2.0"
}

朋友们，我是要在asp.net服务器端直接处理JSON,javascript的处理方法我了解

asp.net读json
function createxmlhttp()
{
   var xmlhttp;
    if (window.ActiveXObject) {
      xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    else if (window.XMLHttpRequest) {
      xmlhttp = new XMLHttpRequest();
    }
    return xmlhttp;
}

3.htm

<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>新建网页 1</title>

<script type="text/javascript" src="json/json.js"></script>
<SCRIPT LANGUAGE="JavaScript" SRC="js/pjs.js"></SCRIPT>
<SCRIPT LANGUAGE="JavaScript" SRC="js/zz.js"></SCRIPT>
<script type="text/javascript">
  var xmlhttp;
//显示内容
  function Car(make, model, year, color)
  {
    this.make = make;
    this.model = model;
    this.year= year;
    this.color = color;
  }
  function getcarobject()
  {
    return new Car("中国","2312","2007","yellow");
  }
  function dojson()
  {
    var car = getcarobject();
    var carstr = car.toJSONString();
    alert(carstr);

    xmlhttp = null;
   xmlhttp = createxmlhttp();
   url = "WebForm1.aspx?dt="+new Date().getTime();
    xmlhttp.open("POST", url, true);
    xmlhttp.onreadystatechange = handleStateChange;
    xmlhttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
    xmlhttp.send(carstr);
  }
  function handleStateChange() {
    if (xmlhttp.readyState == 4) {
      if (xmlhttp.status == 200) {
        document.getElementById("testid").innerHTML = xmlhttp.responseText;
        alert("存档成功！");
      }
    }
  }
  //这表示一个user对象，拥有username, age, info, address 等属性。
  function showJSON() {
    var user =
    {
        "username":"andy",
        "age":20,
        "info": { "tel": "123456", "cellphone": "98765"},
        "address":
            [
                {"city":"beijing","postcode":"222333"},
                {"city":"newyork","postcode":"555666"}
            ]
    }
    alert(user.username);
    alert(user.age);
    alert(user.info.cellphone);
    alert(user.address[0].city);
    alert(user.address[0].postcode);
}
//也可以用JSON来简单的修改数据，修改上面的例子
function showmodJSON() {
    var user =
    {
        "username":"andy",
        "age":20,
        "info": { "tel": "123456", "cellphone": "98765"},
        "address":
            [
                {"city":"beijing","postcode":"222333"},
                {"city":"newyork","postcode":"555666"}
            ]
    }

    alert(user.username);
    alert(user.age);
    alert(user.info.cellphone);
    alert(user.address[0].city);
    alert(user.address[0].postcode);

    user.username = "Tom";
    alert(user.username);
}
//使用eval来转换JSON字符到Object
function myEval() {
    var str = '{ "name": "Violet", "occupation": "character" }';
    var obj = eval('(' + str + ')');
    alert(obj.toJSONString());
}
//或者使用parseJSON()方法
function myEval2() {
    var str = '{ "name": "Violet", "occupation": "character" }';
    var obj = str.parseJSON();
    alert(obj.toJSONString());
}
</script>
</head>

<body>

<form method="POST" action="WebForm1.aspx" target=_blank name="form1">
<p><input type="button" value="显示" name="B3" onclick="showJSON()"></p>
<P><input type="button" value="修改" name="B1" onclick="showmodJSON()"></P>
<p><input type="button" value="showcar" name="B2" onclick="dojson()"></p>
<p><input type="button" value="evar" name="evar" onclick="myEval()"></p>
<p><input type="button" value="parsejoin" name="B5" onclick="myEval2()"></p>
<p><input type="button" value="按钮" name="B6"></p>
<p>
   <div id="testid">
   </div>
</p>
</form>

</body>

</html>

webform1.aspx

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using Jayrock;
using Jayrock.Json;
using Jayrock.Json.Conversion;
using System.IO;
using System.Text;

namespace licai
{
/// <summary>
/// WebForm1 的摘要说明。
/// </summary>
public class WebForm1 : System.Web.UI.Page
{
  private void Page_Load(object sender, System.EventArgs e)
  {
      // 在此处放置用户代码以初始化页面
      Stream instream = Page.Request.InputStream;//获取传入Http实体内容
      BinaryReader br = new BinaryReader(instream, System.Text.Encoding.UTF8);//转换流
      byte[] byt = br.ReadBytes((int)instream.Length);
      string caj = System.Text.Encoding.UTF8.GetString(byt);//转换为string类型
      par pa = (par)JsonConvert.Import(typeof(par),caj);//转换为JSON对应的类
      Response.Write(pa.Make + pa.Year+ pa.Model+ pa.Color);//输出从客户端发送的JSON内容
/*
      Stream instream = Page.Request.InputStream;
      System.IO.StreamReader streamReader = new StreamReader(instream, System.Text.Encoding.GetEncoding("GB2312"));
      //读取流字符串内容
      string content = @streamReader.ReadToEnd();
      JsonTextReader reader = new JsonTextReader(new StringReader(content));
      //以下是转换为数组
      //string[] continents = (string[]) JsonConvert.Import(typeof(string[]),content);
      par pa = (par)JsonConvert.Import(typeof(par),content);

      Response.Clear();
      Response.Buffer= false;
      Response.Charset="GB2312";
      Response.ContentEncoding=System.Text.Encoding.GetEncoding("GB2312");
      Response.Write(pa.Make + pa.Year+ pa.Model+ pa.Color);
*/
/*
      while (reader.Read())
      {
        Response.Write(reader.Text+"<br>");
      }
*/
      Response.End();
  }
    public class par
    {
      private string make, model, year, color;

      public string Make
      {
        get { return make; }
        set { make = value; }
      }

      public string Model
      {
        get { return model; }
        set { model = value; }
      }

      public string Year
      {
        get { return year; }
        set { year = value; }
      }

      public string Color
      {
        get { return color; }
        set { color = value; }
      }

    }


  #region Web 窗体设计器生成的代码
  override protected void OnInit(EventArgs e)
  {
   //
   // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
   //
   InitializeComponent();
   base.OnInit(e);
  }

  /// <summary>
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {
   this.Load += new System.EventHandler(this.Page_Load);
  }
  #endregion
}
}

想问一下 http://www.cnblogs.com/feishan/archive/2008/06/18/1224463.html中的读取JSON那段代码每一句的意思，谢谢！

解决方案 »