C#中怎么解析JSON数据？

Posted 2023-05-03

参考技术A 首先要知道json 的格式 把dataset中datatable表中数据转成json格式 public static string JsonConvert(DataSet ds)

StringBuilder sb = new StringBuilder();
sb.Append("[");
for (int i=0;i<ds.Tables[0].Rows.Count;i++)

sb.Append("");
for (int j = 0; j < ds.Tables[0].Columns.Count; j++)

sb.Append("");
sb.Append(ds.Tables[0].Columns[j].ColumnName);
sb.Append(":\"");
sb.Append(ds.Tables[0].Rows[i][j].ToString().Trim());
sb.Append("\",");

sb.Remove(sb.Length-1,1);
sb.Append(",");

sb.Remove(sb.Length-1,1);
sb.Append("]");
return sb.ToString();
/// <summary>
/// 将Ilist转成json格式
/// </summary>
/// <param name="list"></param>
/// <returns></returns>
public static string JsonConvert(IList<TransBody> list)

try

System.Runtime.Serialization.Json.DataContractJsonSerializer seializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(list.GetType());
using (MemoryStream ms = new MemoryStream())

seializer.WriteObject(ms, list);
return Encoding.UTF8.GetString(ms.ToArray());


catch

return null;

把json格式转成ILIST 格式
public static object ConvertJson(string json ,Type t)

try

System.Runtime.Serialization.Json.DataContractJsonSerializer serializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(t);
using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(json)))

return serializer.ReadObject(ms);


catch

return null;


参考技术B .net 3.5 下有个system.web.script.serialization,有个类，javascriptSerializer 详情参考： http://hi.baidu.com/%B1%F9%D1%A9%D2%F8%C1%AB/blog/item/cfd4cf25cecddc228644f91c.html

c#中怎么解析多层json数据

参考技术A 在.net 2.0中提取这样的json

"name":"lily","age":23,"addr":"city":guangzhou,"province":guangdong

引用命名空间

using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

可以把上面的JSON看成一个对象.你只要写对应的类即可

public class UserInfo



public string name;

public int age;

public address addr;



public class address



public string city;

public string province;


然后在解析的地方这样写:

string jsonData="\"name\":\"lily\",\"age\":23,\"addr\":\"city\":guangzhou,\"province\":guangdong";

UserInfo user=(UserInfo)JsonConvert.DeserializeObject(jsonData, typeof(UserInfo));

得到City的值只要:user.addr.City;

这样实现也行

JObject jsonObj = JObject.Parse(jsonData);

string name=jsonObj ["name"].ToString();

string age=jsonObj ["age"].ToString();

string city=((JObject )jsonObj ["addr"])["city"].ToString();

string province=((JObject )jsonObj ["addr"])["province"].ToString();

如 何这个json是动态的呢？譬如让你输入一个json，如"name":"lily","age":23,"addr": "city":guangzhou,"province":guangdong； 然后让你输入一个对象，如city，然后系统会输出guangzhou这个值，那这样的话，json就是动态生成的了，我想了解有没有读取这样的json 的方法。（注意，json是多级嵌套的。）

就用遍历

public string GetJsonValue(JEnumerable<JToken> jToken,string key)

IEnumerator enumerator = jToken.GetEnumerator();
while (enumerator.MoveNext())

JToken jc = (JToken)enumerator.Current;

if (jc is JObject||((JProperty)jc).Value is JObject)

return GetJsonValue(jc.Children(), key);

else

if (((JProperty)jc).Name == key)


return ((JProperty)jc).Value.ToString();



return null;


在调用的时候:

string jsonData = "\"name\":\"lily\",\"age\":23,\"addr\":\"city\":\"guangzhou\",\"province\":\"guangdong\"";
JObject jsonObj = JObject.Parse(jsonData);
Response.Write(GetJsonValue(jsonObj.Children(), "province"));

如果有多层嵌套的数组

string jsonData = "\"addr\":[\"city\":\"guangzhou\",\"province\":\"guangdong\",\"city\":\"guiyang\",\"province\":\"guizhou\"]";
JObject jsonObj = JObject.Parse(jsonData);
JArray jar = JArray.Parse(jsonObj["addr"].ToString());
JObject j = JObject.Parse(jar[0].ToString());
Response.Write(j["city"]);

JSON转XML

string xmlstr=((XmlDocument)JsonConvert.DeserializeXmlNode(jsonData)).InnerXml.ToString();本回答被提问者采纳