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

namespace NetLibrary
{
    public static class ListExtension
    {
        #region 转JSON文件
        /// <summary>
        /// 转JSON文件
        /// </summary>
        /// <param name="obj">扩展对象</param>
        /// <param name="filePath">文件路径</param>
        public static void ToJSON(this Object obj, string filePath)
        {
            string jsonString = new JavaScriptSerializer().Serialize(obj);
            string DirectoryName = Path.GetDirectoryName(filePath);
            if (System.IO.Directory.Exists(DirectoryName) == false) System.IO.Directory.CreateDirectory(DirectoryName);
            string fileName = Path.GetFileName(filePath);
            File.WriteAllText(filePath, jsonString);
        }
        #endregion
        #region List转DataTable
        /// <summary>
        /// List转DataTable
        /// </summary>
        /// <typeparam name="TResult">对象</typeparam>
        /// <param name="ListModel">扩展对象</param>
        /// <returns></returns>
        public static DataTable ToDataTable<TResult>(this IEnumerable<TResult> ListModel) where TResult : class
        {
            //创建属性的集合
            List<PropertyInfo> pList = new List<PropertyInfo>();
            //获得反射的入口
            Type type = typeof(TResult);
            DataTable dt = new DataTable();
            //把所有的public属性加入到集合 并添加DataTable的列
            Array.ForEach<PropertyInfo>(type.GetProperties(), item =>
            {
                pList.Add(item);
                Type columnType = item.PropertyType;
                if (item.PropertyType.IsGenericType && item.PropertyType.GetGenericTypeDefinition() == typeof(Nullable<>))
                {
                    columnType = item.PropertyType.GetGenericArguments()[0];

                }
                dt.Columns.Add(new DataColumn(item.Name, columnType));
            });
            foreach (var model in ListModel)
            {
                //创建一个DataRow实例
                DataRow row = dt.NewRow();
                //给row 赋值
                pList.ForEach(item =>
                {
                    object value = item.GetValue(model, null);
                    if (value != null) row[item.Name] = value;
                });
                //加入到DataTable
                dt.Rows.Add(row);
            }
            return dt;
        }
        #endregion
        #region List序列化Json
        public static string ToJson<TResult>(this IEnumerable<TResult> list, List<string> ListSerializePropertieName) where TResult : class
        {
            //创建属性的集合
            List<PropertyInfo> pList = new List<PropertyInfo>();
            //获得反射的入口
            Type type = typeof(TResult);
            DataTable dt = new DataTable();
            //把所有的public属性加入到集合 并添加DataTable的列
            Array.ForEach<PropertyInfo>(type.GetProperties(), item =>
            {
                pList.Add(item);
                Type columnType = item.PropertyType;
                if (item.PropertyType.IsGenericType && item.PropertyType.GetGenericTypeDefinition() == typeof(Nullable<>))
                {
                    columnType = item.PropertyType.GetGenericArguments()[0];

                }
                dt.Columns.Add(new DataColumn(item.Name, columnType));
            });
            DateTime time = new DateTime(0x7b2, 1, 1, 0, 0, 0, DateTimeKind.Utc);
            JavaScriptSerializer parseJSON = new JavaScriptSerializer();
            long DatetimeMinTimeTicks = time.Ticks;
            string JsonResult = "[{";
            List<TResult> ListModel = new List<TResult>();
            foreach (var model in ListModel)
            {
                foreach (var item in pList)
                {
                    if (ListSerializePropertieName.Contains(item.Name) == false) continue;
                    object value = item.GetValue(model, null);
                    if (value == null)
                    {
                        JsonResult += "\"" + item.Name + "\":null,";
                        continue;
                    }
                    Type columnType = item.PropertyType;
                    if (item.PropertyType.IsGenericType && item.PropertyType.GetGenericTypeDefinition() == typeof(Nullable<>))
                    {
                        columnType = item.PropertyType.GetGenericArguments()[0];

                    }
                    if (columnType == typeof(string))
                    {
                        string vvv = value.ToString();
                        vvv = vvv.Replace("\r\n", "\\r\\n").Replace("\n", "\\n");
                        JsonResult += "\"" + item.Name + "\":\"" + vvv + "\",";
                        continue;
                    }
                    if (columnType == typeof(DateTime))
                    {
                        DateTime datetime = Convert.ToDateTime(value);
                        JsonResult += "\"" + item.Name + "\":\"\\/Date(" + (long)((datetime.ToUniversalTime().Ticks - DatetimeMinTimeTicks) / 0x2710) + ")\\/\",";
                        continue;
                    }
                    if (columnType == typeof(bool))
                    {
                        JsonResult += "\"" + item.Name + "\":" + value.ToString().ToLower() + ",";
                        continue;
                    }
                    if (columnType == typeof(Int64))
                    {
                        JsonResult += "\"" + item.Name + "\":\"" + value + "\",";
                        continue;
                    }
                    if (columnType == typeof(decimal))
                    {
                        JsonResult += "\"" + item.Name + "\":\"" + Convert.ToDecimal(value).ToString("0.#########") + "\",";
                        continue;
                    }
                    if (columnType == typeof(Int32) || columnType == typeof(Int16) || columnType == typeof(float) || columnType == typeof(short))
                    {
                        JsonResult += "\"" + item.Name + "\":" + value + ",";
                        continue;
                    }
                    JsonResult += "\"" + item.Name + "\":" + parseJSON.Serialize(value) + ",";
                }
            }
            return JsonResult;
        }
        #endregion
       
    }
}