我正在尝试从 Google AJAX 搜索 API 解析一些 JSON 数据。我有 this URL我想把它分解,以便显示结果。我目前已经编写了这段代码,但是对于下一步该做什么我很迷茫,尽管有许多简化 JSON 字符串的示例。
一般来说,作为 C# 和 .NET 的新手,我一直在努力为我的 ASP.NET 页面获得真正的文本输出,因此建议我尝试 JSON.NET。谁能指出我正确的方向,只需编写一些从 Google AJAX 搜索 API 接收 JSON 并将其打印到屏幕上的代码?
编辑:全部修复!所有结果都运行良好。再次感谢 Dreas Grech!
using System;
using System.Data;
using System.Configuration;
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.ServiceModel.Web;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;
using System.IO;
using System.Text;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
GoogleSearchResults g1 = new GoogleSearchResults();
const string json = @"{""responseData"": {""results"":[{""GsearchResultClass"":""GwebSearch"",""unescapedUrl"":""http://www.cheese.com/"",""url"":""http://www.cheese.com/"",""visibleUrl"":""www.cheese.com"",""cacheUrl"":""http://www.google.com/search?q\u003dcache:bkg1gwNt8u4J:www.cheese.com"",""title"":""\u003cb\u003eCHEESE\u003c/b\u003e.COM - All about \u003cb\u003echeese\u003c/b\u003e!."",""titleNoFormatting"":""CHEESE.COM - All about cheese!."",""content"":""\u003cb\u003eCheese\u003c/b\u003e - everything you want to know about it. Search \u003cb\u003echeese\u003c/b\u003e by name, by types of milk, by textures and by countries.""},{""GsearchResultClass"":""GwebSearch"",""unescapedUrl"":""http://en.wikipedia.org/wiki/Cheese"",""url"":""http://en.wikipedia.org/wiki/Cheese"",""visibleUrl"":""en.wikipedia.org"",""cacheUrl"":""http://www.google.com/search?q\u003dcache:n9icdgMlCXIJ:en.wikipedia.org"",""title"":""\u003cb\u003eCheese\u003c/b\u003e - Wikipedia, the free encyclopedia"",""titleNoFormatting"":""Cheese - Wikipedia, the free encyclopedia"",""content"":""\u003cb\u003eCheese\u003c/b\u003e is a food consisting of proteins and fat from milk, usually the milk of cows, buffalo, goats, or sheep. It is produced by coagulation of the milk \u003cb\u003e...\u003c/b\u003e""},{""GsearchResultClass"":""GwebSearch"",""unescapedUrl"":""http://www.ilovecheese.com/"",""url"":""http://www.ilovecheese.com/"",""visibleUrl"":""www.ilovecheese.com"",""cacheUrl"":""http://www.google.com/search?q\u003dcache:GBhRR8ytMhQJ:www.ilovecheese.com"",""title"":""I Love \u003cb\u003eCheese\u003c/b\u003e!, Homepage"",""titleNoFormatting"":""I Love Cheese!, Homepage"",""content"":""The American Dairy Association\u0026#39;s official site includes recipes and information on nutrition and storage of \u003cb\u003echeese\u003c/b\u003e.""},{""GsearchResultClass"":""GwebSearch"",""unescapedUrl"":""http://www.gnome.org/projects/cheese/"",""url"":""http://www.gnome.org/projects/cheese/"",""visibleUrl"":""www.gnome.org"",""cacheUrl"":""http://www.google.com/search?q\u003dcache:jvfWnVcSFeQJ:www.gnome.org"",""title"":""\u003cb\u003eCheese\u003c/b\u003e"",""titleNoFormatting"":""Cheese"",""content"":""\u003cb\u003eCheese\u003c/b\u003e uses your webcam to take photos and videos, applies fancy special effects and lets you share the fun with others. It was written as part of Google\u0026#39;s \u003cb\u003e...\u003c/b\u003e""}],""cursor"":{""pages"":[{""start"":""0"",""label"":1},{""start"":""4"",""label"":2},{""start"":""8"",""label"":3},{""start"":""12"",""label"":4},{""start"":""16"",""label"":5},{""start"":""20"",""label"":6},{""start"":""24"",""label"":7},{""start"":""28"",""label"":8}],""estimatedResultCount"":""14400000"",""currentPageIndex"":0,""moreResultsUrl"":""http://www.google.com/search?oe\u003dutf8\u0026ie\u003dutf8\u0026source\u003duds\u0026start\u003d0\u0026hl\u003den-GB\u0026q\u003dcheese""}}, ""responseDetails"": null, ""responseStatus"": 200}";
g1 = JSONHelper.Deserialise<GoogleSearchResults>(json);
Response.Write(g1.content);
}
}
public class JSONHelper
{
public static T Deserialise<T>(string json)
{
T obj = Activator.CreateInstance<T>();
MemoryStream ms = new MemoryStream(Encoding.Unicode.GetBytes(json));
DataContractJsonSerializer serialiser = new DataContractJsonSerializer(obj.GetType());
ms.Close();
return obj;
}
}
/// Deserialise from JSON
[Serializable]
public class GoogleSearchResults
{
public GoogleSearchResults() { }
public GoogleSearchResults(string _unescapedUrl, string _url, string _visibleUrl, string _cacheUrl, string _title, string _titleNoFormatting, string _content)
{
this.unescapedUrl = _unescapedUrl;
this.url = _url;
this.visibleUrl = _visibleUrl;
this.cacheUrl = _cacheUrl;
this.title = _title;
this.titleNoFormatting = _titleNoFormatting;
this.content = _content;
}
string _unescapedUrl;
string _url;
string _visibleUrl;
string _cacheUrl;
string _title;
string _titleNoFormatting;
string _content;
[DataMember]
public string unescapedUrl
{
get { return _unescapedUrl; }
set { _unescapedUrl = value; }
}
[DataMember]
public string url
{
get { return _url; }
set { _url = value; }
}
[DataMember]
public string visibleUrl
{
get { return _visibleUrl; }
set { _visibleUrl = value; }
}
[DataMember]
public string cacheUrl
{
get { return _cacheUrl; }
set { _cacheUrl = value; }
}
[DataMember]
public string title
{
get { return _title; }
set { _title = value; }
}
[DataMember]
public string titleNoFormatting
{
get { return _titleNoFormatting; }
set { _titleNoFormatting = value; }
}
[DataMember]
public string content
{
get { return _content; }
set { _content = value; }
}
}
代码当前可以完美编译和运行,但没有返回任何结果。有人可以帮我返回我需要的东西,准备好打印到屏幕上的结果吗?
编辑:
Json.NET 使用与上述示例相同的 JSON 和类。
GoogleSearchResults g1 = JsonConvert.DeserializeObject<GoogleSearchResults>(json);
链接:Serializing and Deserializing JSON with Json.NET
C# - parsing json formatted data into nested hashtables
Parse JSON array
最佳答案
[更新]
我刚刚意识到为什么您没有收到返回结果...您的 Deserialize
方法中缺少一行。您忘记将结果分配给您的 obj
:
public static T Deserialize<T>(string json)
{
using (MemoryStream ms = new MemoryStream(Encoding.Unicode.GetBytes(json)))
{
DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(T));
return (T)serializer.ReadObject(ms);
}
}
另外,仅供引用,这里是Serialize
方法:
public static string Serialize<T>(T obj)
{
DataContractJsonSerializer serializer = new DataContractJsonSerializer(obj.GetType());
using (MemoryStream ms = new MemoryStream())
{
serializer.WriteObject(ms, obj);
return Encoding.Default.GetString(ms.ToArray());
}
}
编辑
如果你想使用 Json.NET,这里有与上面代码等效的 Serialize/Deserialize 方法..
反序列化:
JsonConvert.DeserializeObject<T>(string json);
序列化:
JsonConvert.SerializeObject(object o);
这已经是 Json.NET 的一部分,因此您可以在 JsonConvert 类上调用它们。
链接:Serializing and Deserializing JSON with Json.NET
现在,您获得 StackOverflow 的原因是您的 Properties
。
以这个为例:
[DataMember]
public string unescapedUrl
{
get { return unescapedUrl; } // <= this line is causing a Stack Overflow
set { this.unescapedUrl = value; }
}
请注意,在 getter
中,您正在返回实际的属性(即属性的 getter 一遍又一遍地调用自身),因此您正在创建无限递归。
属性(在 2.0 中)应该这样定义:
string _unescapedUrl; // <= private field
[DataMember]
public string unescapedUrl
{
get { return _unescapedUrl; }
set { _unescapedUrl = value; }
}
您有一个私有(private)字段,然后在 getter 中返回该字段的值,并在 setter 中设置该字段的值。
顺便说一句,如果您使用的是 3.5 框架,您可以这样做并避免使用支持字段,并让编译器来处理:
public string unescapedUrl { get; set;}
https://stackoverflow.com/questions/1212344/