TList、DataTable To Json

        public static string Obj2Json<T>(T data)
        {
            try
            {
                System.Runtime.Serialization.Json.DataContractJsonSerializer serializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(data.GetType());
                using (MemoryStream ms = new MemoryStream())
                {
                    serializer.WriteObject(ms, data);
                    return Encoding.UTF8.GetString(ms.ToArray());
                }
            }
            catch
            {
                return null;
            }
        }

        public static Object Json2Obj(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;
            }
        }

        public static string DataTable2Json(DataTable dt)
        {
            if (dt.Rows.Count == 0)
            {
                return "";
            }

            StringBuilder jsonBuilder = new StringBuilder();
            // jsonBuilder.Append("{");
            //jsonBuilder.Append(dt.TableName.ToString());
            jsonBuilder.Append("[");//转换成多个model的形式
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                jsonBuilder.Append("{");
                for (int j = 0; j < dt.Columns.Count; j++)
                {
                    jsonBuilder.Append("\"");
                    jsonBuilder.Append(dt.Columns[j].ColumnName);
                    jsonBuilder.Append("\":\"");
                    jsonBuilder.Append(dt.Rows[i][j].ToString());
                    jsonBuilder.Append("\",");
                }
                jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
                jsonBuilder.Append("},");
            }
            jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
            jsonBuilder.Append("]");
            //  jsonBuilder.Append("}");
            return jsonBuilder.ToString();
        }