using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace Common
{
    public class BulkInsert
    {
        private string connectionString;

        public BulkInsert(string _con)
        {
            connectionString = ConfigurationManager.ConnectionStrings[_con].ConnectionString;
        }

        public BulkInsert(string _con, bool DESE)
        {
            connectionString = DESEncrypt.Decrypt(ConfigurationManager.ConnectionStrings[_con].ConnectionString);
        }

        public void WriteToServer<T>(List<T> list, string TableName)
        {

            using (SqlConnection destinationConnection = new SqlConnection(connectionString))
            {

                DataTable dt = list.ToDataTable();

                destinationConnection.Open();
                using (SqlBulkCopy bulkCopy = new SqlBulkCopy(destinationConnection))
                {
                    bulkCopy.DestinationTableName = TableName;
                    bulkCopy.NotifyAfter = 30000;
                    try
                    {
                        bulkCopy.WriteToServer(dt);

                        Console.WriteLine("{0}插入{1}条数据", TableName, list.Count);
                    }
                    catch (Exception ex)
                    {
                        //Console.WriteLine(ex.Message);
                        throw ex;
                    }
                    finally
                    {

                    }
                }
            }

        }

    }

    public static class DataTableHelper
    {

        public static DataTable ToDataTable<T>(this List<T> list)
        {

            //创建属性的集合   
            List<PropertyInfo> pList = new List<PropertyInfo>();
            //获得反射的入口   

            Type type = typeof(T);
            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(), p => { pList.Add(p); dt.Columns.Add(p.Name, p.PropertyType); });
            foreach (var item in list)
            {
                //创建一个DataRow实例   
                DataRow row = dt.NewRow();
                //给row 赋值   
                pList.ForEach(p => row[p.Name] = p.GetValue(item, null));
                //加入到DataTable   
                dt.Rows.Add(row);
            }
            return dt;
        }

        public static IEnumerable<T> Distinct<T, V>(this IEnumerable<T> source, Func<T, V> keySelector)
        {
            return source.Distinct(new CommonEqualityComparer<T, V>(keySelector));
        }
    }
    public class CommonEqualityComparer<T, V> : IEqualityComparer<T>
    {
        private Func<T, V> keySelector;

        public CommonEqualityComparer(Func<T, V> keySelector)
        {
            this.keySelector = keySelector;
        }

        public bool Equals(T x, T y)
        {
            return EqualityComparer<V>.Default.Equals(keySelector(x), keySelector(y));
        }

        public int GetHashCode(T obj)
        {
            return EqualityComparer<V>.Default.GetHashCode(keySelector(obj));
        }
    }
}

SqlBulkCopy 帮助类