在ASP.NET WEB应用程序中使用的一个JsonHelper

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Script.Serialization;
using System.Data;
using System.Text;

namespace JQuery
{
    public class JsonHelper
    {
        #region 返回一个Json类型
        /// <summary>
        /// 返回一个Json字符串
        /// </summary>
        /// <param name="obj">传入泛型集合</param>
        /// <returns></returns>
        public static string ObjectToJson(object obj)
        {
            JavaScriptSerializer jss = new JavaScriptSerializer();
            return jss.Serialize(obj);
        }

        /// <summary>
        /// 返回一个List泛型集合
        /// </summary>
        /// <param name="dt">传入一个DataTable</param>
        /// <returns></returns>
        public static List<Dictionary<string, object>> DataTableToList(DataTable dt)
        {
            List<Dictionary<string, object>> listDic = new List<Dictionary<string, object>>();
            foreach (DataRow dr in dt.Rows)
            {
                Dictionary<string, object> dic = new Dictionary<string, object>();
                foreach (DataColumn dc in dt.Columns)
                {
                    dic.Add(dc.ColumnName, dr[dc.ColumnName]);
                }
                listDic.Add(dic);
            }
            return listDic;
        }

        public static string DataTableToJson(DataTable dt)
        {
            return ObjectToJson(DataTableToList(dt));
        }
        #endregion

        #region 返回带名字的Jsoin
        /// <summary>
        /// 
        /// </summary>
        /// <param name="name"></param>
        /// <param name="dt"></param>
        /// <returns></returns>
        public static string DataTableToJsonp(string name, DataTable dt)
        {
            string JsonName = name;
            StringBuilder Json = new StringBuilder("{\"" + JsonName + "\":[");
            if (dt.Rows.Count > 0)
            {
                foreach (DataRow row in dt.Rows)
                {
                    Json.Append("{");
                    foreach (DataColumn column in dt.Columns)
                    {
                        Json.Append("\"" + column.ColumnName + "\":\"" + row[column.ColumnName].ToString() + "\",");
                    }
                    Json.Remove(Json.Length - 1, 1);
                    Json.Append("},");
                }
                Json.Remove(Json.Length - 1, 1);
            }
            Json.Append("]}");

            return Json.ToString();
        }

        #endregion

        /// <summary>
        /// 传人一张表 然后转换为json格式数据
        /// json格式例：{table:[{'id':'soo1','name':'cys','age':'21'},{'id':'soo2','name':'cys','age':'21'},{'id':'soo3','name':'cys','age':'21'}]}
        /// </summary>
        /// <param name="table"></param>
        /// <returns>返回json格式数据</returns>
        public static string TableToJson(DataTable table)
        {
            StringBuilder output = new StringBuilder();
            if (table.Rows.Count > 0)//判断是否有数据
            {
                output.Append("{table:[");
                //循环table拼接json数据
              for (int i = 0; i < table.Rows.Count; i++)
              {     
                output.Append("{");
                   for (int j = 0; j < table.Columns.Count; j++)
                    {    
                       output.Append("'"+table.Columns[j].ColumnName+"':'"+table.Rows[i][j]+"',");
                    }
                  //移除最后一个，
                   output.Remove(output.Length-1,output.Length);
                   output.Append("},");
                }                
              //移除最后一个，
              output.Remove(output.Length - 1, output.Length);
              output.Append("]}");
            }
            else
            {
                return "";
            }
            return output.ToString();//返回json格式数据
        }


        /// <summary>
        /// 把一个表转化成字符串
        /// </summary>
        /// <param name="table">要转换的表</param>
        /// <param name="haveHend">是否保存数据库的表头 true：保存 false：不保存</param>
        /// <returns>返回一个html表的字符串</returns>
        public static string TableToTableStr(DataTable table,bool haveHend)
        {            
            if (table.Rows.Count > 0)
            {
                StringBuilder output = new StringBuilder();               
                output.Append("<table border='1'>");
                if (haveHend)
                { //构建表头
                    foreach (DataColumn item in table.Columns)
                    {
                        output.Append("<th>" + item.ColumnName + "</th>");
                    }
                }                
                //产生表体
                foreach (DataRow row in table.Rows)
                {
                    output.Append("<tr>");
                    foreach (DataColumn clo in table.Columns)
                    {
                        output.Append("<td>"+row[clo.ColumnName].ToString()+"</td>");
                    }
                    output.Append("</tr>");
                }
                output.Append("</table>");
                return output.ToString();
            }
            else
            {
                return "no data!!";
            }
           
        }
    }
}