Question

C# 怎么将json 转换成 datatable

[
{"hasChildNode":"1","nodeId":"200","nodeName":"医药","nodeType":"文件夹"},
{"hasChildNode":"1","nodeId":"234","nodeName":"财会","nodeType":"文件夹"},
{"hasChildNode":"1","nodeId":"235","nodeName":"建筑","nodeType":"文件夹"}, {"hasChildNode":"1","nodeId":"239","nodeName":"其它","nodeType":"文件夹"}
]
每个大括号相当于一行数据 冒号前字段相当于 列名，后为列值

怎么解出呢

Answer 1

主要包含两个方法：
1. 获取的DataTable 对象 转换为Json 字符串
2. Json 字符串 转换为 DataTable数据集合

#region DataTable 转换为Json字符串实例方法
/// <summary>
/// GetClassTypeJosn 的摘要说明
/// </summary>
public class GetClassTypeJosn : IHttpHandler
{
/// <summary>
/// 文件名:DataTable 和Json 字符串互转
/// 版权所有:Copyright (C) Create Family Wealth liangjw
/// 创建标示：2013-08-03
/// </summary>
//用法说明实例
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "application/json";
context.Response.Charset = "utf-8";
HttpRequest req = context.Request;
string method = req["method"].ToStr().ToLower();

//获取合同明细列表 DataTable 转换为Json字符串
if (method == "txtdate")
{
string json = "";
BO.MakeContractMx bll = new MakeContractMx();
DataSet ds = bll.GetDataTable();
if (ds.Tables.Count > 0)
{
json =ToJson(ds.Tables[0]);
}
context.Response.Write(json);
return;
}

}

public bool IsReusable
{
get
{
return false;
}
}
}

#endregion

#region Json字符串转换为DataTable 实例方法

public DataTable JsonToDataTable(json)
{
DataTable dt= ToDataTable(json);
return dt;
}

#endregion

#region DataTable 转换为Json 字符串
/// <summary>
/// DataTable 对象 转换为Json 字符串
/// </summary>
/// <param name="dt"></param>
/// <returns></returns>
public static string ToJson(this DataTable dt)
{
JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值
ArrayList arrayList = new ArrayList();
foreach (DataRow dataRow in dt.Rows)
{
Dictionary<string, object> dictionary = new Dictionary<string, object>(); //实例化一个参数集合
foreach (DataColumn dataColumn in dt.Columns)
{
dictionary.Add(dataColumn.ColumnName, dataRow[dataColumn.ColumnName].ToStr());
}
arrayList.Add(dictionary); //ArrayList集合中添加键值
}

return javaScriptSerializer.Serialize(arrayList); //返回一个json字符串
}
#endregion

#region Json 字符串 转换为 DataTable数据集合
/// <summary>
/// Json 字符串 转换为 DataTable数据集合
/// </summary>
/// <param name="json"></param>
/// <returns></returns>
public static DataTable ToDataTable(this string json)
{
DataTable dataTable = new DataTable(); //实例化
DataTable result;
try
{
JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值
ArrayList arrayList = javaScriptSerializer.Deserialize<ArrayList>(json);
if (arrayList.Count > 0)
{
foreach (Dictionary<string, object> dictionary in arrayList)
{
if (dictionary.Keys.Count<string>() == 0)
{
result = dataTable;
return result;
}
if (dataTable.Columns.Count == 0)
{
foreach (string current in dictionary.Keys)
{
dataTable.Columns.Add(current, dictionary[current].GetType());
}
}
DataRow dataRow = dataTable.NewRow();
foreach (string current in dictionary.Keys)
{
dataRow[current] = dictionary[current];
}

dataTable.Rows.Add(dataRow); //循环添加行到DataTable中
}
}
}
catch
{
}
result = dataTable;
return result;
}
#endregion

#region 转换为string字符串类型
/// <summary>
/// 转换为string字符串类型
/// </summary>
/// <param name="s">获取需要转换的值</param>
/// <param name="format">需要格式化的位数</param>
/// <returns>返回一个新的字符串</returns>
public static string ToStr(this object s, string format = "")
{
string result = "";
try
{
if (format == "")
{
result = s.ToString();
}
else
{
result = string.Format("{0:" + format + "}", s);
}
}
catch
{
}
return result;
}
#endregion

Answer 2

/// <summary>   
/// 将 Json 解析成 DateTable。  
/// Json 数据格式如: 
///     {table:[{column1:1,column2:2,column3:3},{column1:1,column2:2,column3:3}]} /// </summary>   
/// <param name="strJson">要解析的 Json 字符串</param>   
/// <returns>返回 DateTable</returns>   
public static DataTable JsonToDataTable(string strJson)
{
 // 取出表名   
 var rg = new Regex(@"(?<={)[^:]+(?=:\[)", RegexOptions.IgnoreCase);
 string strName = rg.Match(strJson).Value;
 DataTable tb = null;

 // 去除表名   
 strJson = strJson.Substring(strJson.IndexOf("[") + 1);
 strJson = strJson.Substring(0, strJson.IndexOf("]"));

 // 获取数据   
 rg = new Regex(@"(?<={)[^}]+(?=})");
 MatchCollection mc = rg.Matches(strJson);
 for (int i = 0; i < mc.Count; i++)
 {
  string strRow = mc[i].Value;
  string[] strRows = strRow.Split(',');
  // 创建表   
  if (tb == null)
  {
   tb = new DataTable();
   tb.TableName = strName;
   foreach (string str in strRows)
   {
    var dc = new DataColumn();
    string[] strCell = str.Split(':');
    dc.ColumnName = strCell[0].Replace("\"", "");
    tb.Columns.Add(dc);
   }
   tb.AcceptChanges();
  }
  // 增加内容   
  DataRow dr = tb.NewRow();
  for (int j = 0; j < strRows.Length; j++)
  {
   dr[j] = strRows[j].Split(':')[1].Replace("\"", "");
  }
  tb.Rows.Add(dr);
  tb.AcceptChanges();
 }
 return tb;
}

引入命名空间 System.Text.RegularExpressions。

Answer 3

循环 jason 自己转吧