DataTable转Json方法

public static string CreateJsonParameters(DataTable dt)
        {
            /**//**/
            /**//* /****************************************************************************
          * Without goingin to the depth of the functioning of this Method, i will try to give an overview
          * As soon as this method gets a DataTable it starts to convert it into JSON String,
          * it takes each row and in each row it grabs the cell name and its data.
          * This kind of JSON is very usefull when developer have to have Column name of the .
          * Values Can be Access on clien in this way. OBJ.HEAD[0].<ColumnName>
          * NOTE: One negative point. by this method user will not be able to call any cell by its index.
         * *************************************************************************/
            StringBuilder JsonString = new StringBuilder();
            //Exception Handling        
            if (dt != null && dt.Rows.Count > 0)
            {
                JsonString.Append("{ ");
                JsonString.Append("\"T_blog\":[ ");
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    JsonString.Append("{ ");
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        if (j < dt.Columns.Count - 1)
                        {
                            JsonString.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\",");
                        }
                        else if (j == dt.Columns.Count - 1)
                        {
                            JsonString.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\"");
                        }
                    }
                    /**//**/
                    /**//*end Of String*/
                    if (i == dt.Rows.Count - 1)
                    {
                        JsonString.Append("} ");
                    }
                    else
                    {
                        JsonString.Append("}, ");
                    }
                }
                JsonString.Append("]}");
                return JsonString.ToString();
            }
            else
            {
                return null;
            }
        }

{"T_blog":
  [
   {"id":"14","title":"北京奥运开幕式","addtime":"2008-08-08"},
   {"id":"15","title":"网络文化","addtime":"2008-09-12"},
   {"id":"17","title":"北京下雨了","addtime":"2008-09-19"},
   {"id":"21","title":"深圳地铁通了","addtime":"2008-09-25"}
  ]
}

  /// <summary>
    /// 将一个数据表转换成一个JSON字符串，在客户端可以直接转换成二维数组。
    /// </summary>
    /// <param name="source">需要转换的表。</param>
    /// <returns></returns>
    public static string DataTableToJson(DataTable source)
    {
        if (source.Rows.Count == 0)
            return "";
        StringBuilder sb = new StringBuilder("[");
        foreach (DataRow row in source.Rows)
        {
            sb.Append("[");
            for (int i = 0; i < source.Columns.Count; i++)
            {
                sb.Append('"' + row[i].ToString() + "\",");
            }
            sb.Remove(sb.Length - 1, 1);
            sb.Append("],");
        }
        sb.Remove(sb.Length - 1, 1);
        sb.Append("]");
        return sb.ToString();
    }


    /// <summary>
    /// 反回JSON数据到前台
    /// </summary>
    /// <param name="dt">数据表</param>
    /// <returns>JSON字符串</returns>
    public string CreateJsonParameters(DataTable dt)
    {
        StringBuilder JsonString = new StringBuilder();
        //Exception Handling        
        if (dt != null && dt.Rows.Count > 0)
        {
            JsonString.Append("{ ");
            JsonString.Append("\"TableInfo\":[ ");
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                JsonString.Append("{ ");
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    if (j < dt.Columns.Count - 1)
                    {
                        JsonString.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\",");
                    }
                    else if (j == dt.Columns.Count - 1)
                    {
                        JsonString.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\"");
                    }
                }
                /**/
                /*end Of String*/
                if (i == dt.Rows.Count - 1)
                {
                    JsonString.Append("} ");
                }
                else
                {
                    JsonString.Append("}, ");
                }
            }
            JsonString.Append("]}");
            return JsonString.ToString();
        }
        else
        {
            return null;
        }
    }