#define ASYNC
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Text;
using System.Threading.Tasks;
using static System.Math;
namespace NewCharp6
{class Program{static void Main(string[] args){//Initilizers for auto properties and function with lambdavar salesOrder = new SalesOrder();Console.WriteLine("Begin to Test New In C# 6.0");Console.WriteLine("=====================Auto Init Property  lambda In A class=======================");Console.WriteLine("OrderNo:" + salesOrder.OrderNo);Console.WriteLine("OrderCode:" + salesOrder.OrderCode);Console.WriteLine("OrderInfo:" + salesOrder.OrderInfo);Console.WriteLine("GetOrderInfo:" + salesOrder.GetOrderInfo());Console.WriteLine("=====================Test Null Conditional Operators=======================");Console.WriteLine("Here Will Output Null Value.............");SalesInovice salesInvoice = new SalesInovice();Console.WriteLine(salesInvoice.OrderList?[0].OrderNo);//sample OperatorConsole.WriteLine(salesInvoice.salesReturn?.returnCode);//sample Operator//Initializers the Orders And RetutnConsole.WriteLine("Here Will Output Actual Value After Initializer the Object.............");salesOrder.OrderNo = Guid.NewGuid();salesOrder.OrderCode = "OS0001";salesInvoice.OrderList = new List<SalesOrder>();salesInvoice.OrderList.Add(salesOrder);salesInvoice.salesReturn = new SalesReturn();salesInvoice.salesReturn.returnNo = Guid.NewGuid();salesInvoice.salesReturn.returnCode = "RT0001";Console.WriteLine(salesInvoice.OrderList?[0].OrderNo + ":" + salesInvoice.OrderList?[0].OrderCode);Console.WriteLine(salesInvoice.salesReturn?.returnNo + ":" + salesInvoice.salesReturn?.returnCode);//Index InitializersConsole.WriteLine("Initializer An Collections With Index .............");var returnDictionary = new Dictionary<int, SalesReturn>() { [0] = new SalesReturn() { returnNo = Guid.NewGuid(), returnCode = "RT001" }, [1] = new SalesReturn { returnNo = Guid.NewGuid(), returnCode = "RT002" } };Console.WriteLine("Here Will Output the Dictionary：" + returnDictionary[0]?.returnNo + returnDictionary[0]?.returnCode);var returnStrDictionary = new Dictionary<String, SalesReturn>() { ["One"] = new SalesReturn { returnNo = Guid.NewGuid(), returnCode = "RT001" }, ["Two"] = new SalesReturn { returnNo = Guid.NewGuid(), returnCode = "RT002" } };Console.WriteLine("Here Will Output the Dictionary：" + returnStrDictionary["One"]?.returnNo + returnStrDictionary["One"]?.returnCode);//Here Will Output All Object in the Dictionarys foreach (KeyValuePair<string, SalesReturn> item in returnStrDictionary){Console.WriteLine("Key:" + item.Key + string.Format("   {0}-{1}", item.Value.returnNo, item.Value.returnCode));}//Here will Output the math function Directly Before we Will use System.Math.abs But Now Just use abs Console.WriteLine("=====================Using static NameSpace=======================");Console.WriteLine("using static System.Math at the head firse");Console.WriteLine("Output the abs value:" + Abs(-7));//Exception Filter In C# 6.0#if ASPNETConsole.WriteLine("=====================Exception Filter In C# 6.0=======================");try{try{Console.WriteLine("begin to throw ASPNET EXCEPTION.........");throw new ExceptionHander("ASP.Net Exception");}catch (ExceptionHander ex) when (ExceptionHander.CheckEx(ex)){//ASPNET EXCEPTION WILL NOT CATCH HEREConsole.WriteLine("Exception Type:" + ex.Message + "Was Catch the Other was Missing .......");}}catch (ExceptionHander ex){//ASPNET EXCEPTION WILL CATCH HEREConsole.WriteLine(ex.Message);}
#elif DATABASEtry{try{Console.WriteLine("begin to throw DATABASE EXCEPTION.........");throw new ExceptionHander((int)ExType.DATABASE, "DataBase Exception");}catch (ExceptionHander ex) when (ExceptionHander.CheckEx(ex)){Console.WriteLine("Exception Type:" + ex.Message + "Was Catch the Other was Missing .......");}}catch (ExceptionHander ex){//DATABASE EXCEPTION WILL CATCH HEREConsole.WriteLine(ex.Message);}#elif ASYNCConsole.WriteLine("========Begin To Test async in catch and finally blocks(C#6.0 Only)===============");try{throw new Exception("Error Occur");}catch (Exception ex){//TODO can't use the async In Mian // var returnAsync = await ProcessWrite(ex.Message);}
#endifConsole.ReadKey();}protected static SalesOrder GetSales(){SalesOrder salesOrder = new SalesOrder();salesOrder.OrderCode = "SO001";return salesOrder;}//async read and writepublic async void ProcessWrite(string text){string filePath = System.Environment.CurrentDirectory + "commonLog.txt";await WriteTextAsync(filePath, text);}private async Task WriteTextAsync(string filePath, string text){byte[] encodedText = Encoding.Unicode.GetBytes(text);using (FileStream sourceStream = new FileStream(filePath,FileMode.Append, FileAccess.Write, FileShare.None,bufferSize: 4096, useAsync: true)){await sourceStream.WriteAsync(encodedText, 0, encodedText.Length);};}public async void ProcessRead(){string filePath = @"temp2.txt";if (File.Exists(filePath) == false){Debug.WriteLine("file not found: " + filePath);}else{try{string text = await ReadTextAsync(filePath);Debug.WriteLine(text);}catch (Exception ex){Debug.WriteLine(ex.Message);}}}private async Task<string> ReadTextAsync(string filePath){using (FileStream sourceStream = new FileStream(filePath,FileMode.Open, FileAccess.Read, FileShare.Read,bufferSize: 4096, useAsync: true)){StringBuilder sb = new StringBuilder();byte[] buffer = new byte[0x1000];int numRead;while ((numRead = await sourceStream.ReadAsync(buffer, 0, buffer.Length)) != 0){string text = Encoding.Unicode.GetString(buffer, 0, numRead);sb.Append(text);}return sb.ToString();}}}public class SalesOrder{public Guid OrderNo { get; set; } = new Guid();public String OrderCode { get; set; }public Int32 Quanlity { get; set; }public double UnitPrice { get; set; }public String OrderInfo => string.Format("lambda to property demo {0}:{1}", OrderNo, OrderCode);//lambda for properyies public String GetOrderInfo() => string.Format("lambda to function demo {0}:{1}", OrderNo, OrderCode);//lambda for functions }public class SalesInovice{public Guid InvoiceNo { get; set; }public String InvoiceCode { get; set; }public List<SalesOrder> OrderList { get; set; }public SalesReturn salesReturn { get; set; }}public class SalesReturn{public Guid returnNo { get; set; }public String returnCode { get; set; }}public class ExceptionHander : Exception{public int TypeofException { get; set; } = (int)ExType.ASPNET;public string Msg { get; set; }public ExceptionHander(int Type, string Message) : this(Message){TypeofException = Type;}public ExceptionHander(String msg){Msg = msg;}public static Boolean CheckEx(ExceptionHander ex){if (ex.TypeofException.Equals(ExType.DATABASE)){return true;}else{return false;}}}public enum ExType{DATABASE = 0,ASPNET = 1}
}

   public class SalesOrder{public Guid OrderNo { get; set; } = new Guid();public String OrderCode { get; set; }public Int32 Quanlity { get; set; }public double UnitPrice { get; set; }public String OrderInfo => string.Format("lambda to property demo {0}:{1}", OrderNo, OrderCode);//lambda for properyies public String GetOrderInfo() => string.Format("lambda to function demo {0}:{1}", OrderNo, OrderCode);//lambda for functions }

 Console.WriteLine(salesInvoice.OrderList?[0].OrderNo + ":" + salesInvoice.OrderList?[0].OrderCode);
Console.WriteLine(salesInvoice.salesReturn?.returnNo + ":" + salesInvoice.salesReturn?.returnCode);

  Console.WriteLine("Initializer An Collections With Index .............");var returnDictionary = new Dictionary<int, SalesReturn>() { [0] = new SalesReturn() { returnNo = Guid.NewGuid(), returnCode = "RT001" }, [1] = new SalesReturn { returnNo = Guid.NewGuid(), returnCode = "RT002" } };Console.WriteLine("Here Will Output the Dictionary：" + returnDictionary[0]?.returnNo + returnDictionary[0]?.returnCode);

  try{try{Console.WriteLine("begin to throw DATABASE EXCEPTION.........");throw new ExceptionHander((int)ExType.DATABASE, "DataBase Exception");}catch (ExceptionHander ex) when (ExceptionHander.CheckEx(ex)){Console.WriteLine("Exception Type:" + ex.Message + "Was Catch the Other was Missing .......");}}catch (ExceptionHander ex){//DATABASE EXCEPTION WILL CATCH HEREConsole.WriteLine(ex.Message);}