c# async tutorial

Let's name C # asynchronous programming Async again, This article is copyrighted by the bloggers and the author Wu Shuang himself. Repost and crawler must indicate the source in the prominent position: http://www.cnblogs.com/tdws Half a year ago, I translated a series of bad asynchronous programming articles, in a conventional asynchronous Syntax: "at some time in the future," I will re-translate

In Synchronous Programming, once an error occurs, an exception is thrown. We can use try... Catch is used to catch exceptions, but uncaptured exceptions are continuously passed up to form a simple and unified error handling mechanism. However, for asynchronous programming, exception handling has always been troublesome, which is also one of the advantages of async, await, Jscex, and other asynchronous programming models in

This article mainly introduces the knowledge of Thread,task,async/await,iasyncresult in C #. Have a certain reference value, follow the small series below to see it Speaking of Async, thread,task,async/await,iasyncresult these things must not be around, and today we will talk about them in turn 1. Threads (thread) The

C # synchronous and asynchronous understanding, including await and async in 5.0 (learning notes ), Previously, I used a synchronization thread, that is, the load event first written into the image, and then processed the database call in it. Later I met some old code in the company's software. When I first added functionality to the old code, I wanted to use the database data to assign some values to the i

. // - Control resumes here when getStringTask is complete. // - The await operator then retrieves the string result from getStringTask. string urlContents = await getStringTask; // The return statement specifies an integer result. // Any methods that are awaiting AccessTheWebAsync retrieve the length value. return urlContents.Length; } void DoIndependentWork()

C #~ Asynchronous programming continued ~. Net4.5 main await async applications, I have written two articles about asynchronous programming before. For details, go to C #~ Asynchronous programming and C #~ Use of asynchronous programming in projects . Each version of net has its own proprietary technology, such. deleg

C # Async and Await usage, 1 using System; 2 using System. collections. generic; 3 using System. linq; 4 using System. text; 5 using System. threading; 6 using System. threading. tasks; 7 8 namespace CloudLearning. UI 9 {10 class Program11 {12 static void Main (string [] args) 13 {14 AsyncPrintHelloWorld (); 15 Console. readLine (); 16} 17 18 public async static

= HotelBusiness.Instance.QueryHotelList (parameter); //Blocking IIS Threadsreturn result;}2. Add only a few keywords, it becomes asynchronous processing[HttpGet]Public Async taskhotellistresponse> List (...{...Return await Task.Factory.StartNew (() = HotelBusiness.Instance.QueryHotelList (parameter)); Operation of resource consumption, moved to asynchronous}3. After the modified code runs, the current IIS thread ID is 9 When a request comes in4. An

Transferred from: https://www.cnblogs.com/doforfuture/p/6293926.htmlSpeaking of Async, thread,task,async/await,iasyncresult these things must not be around, and today we will talk about them in turn1. Threads (thread)The meaning of multithreading is that in an application, multiple execution parts can be executed concurrently, for more time-consuming operations (such as IO, database operations), or for oper

public class MyClass{Public MyClass (){Displayvalue (); There's no blocking.System.Diagnostics.Debug.WriteLine ("MyClass () End.");}Public task{Return Task.run (() ={for (int i = 0; i {NUM1 = num1/num2;}return NUM1;});}Public async void Displayvalue (){Double result = await Getvalueasync (1234.5, 1.01);//This will open a new thread to process the Getvalueasync task, then return the method immediatelyAll code after this is encapsulated as a delegate, w

usingSystem;usingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;usingSystem.Threading;namespaceAsync Thread {classAsynchronous {Private inti =0; Public voidShow () { for(inti =0; I 5; i++) { //The system comes with a delegate (parameter has no return value, parameter has a return value)Action action =NewAction (Index);//callback function (the second parameter of an asynchronous execution delegate)AsyncCallbackAsync=NewAsyncCallback ((x) = Console.WriteLine ("I am the c

."); } Public Async voidAsynctask () {stringx =awaitAsyncTask2 (); ShowMsg (x); Thread.Sleep ( +); ShowMsg ("Asynctask.end"); } Public Asynctaskstring>AsyncTask2 () {return awaitTask.run (() = { //simulate a process with a very large workloadShowMsg ("run.. Begininvoke.start."); Random Rd=NewRandom (); Thread.Sleep (Rd. Next ( the,6000)); ShowMsg ("run.. Begininvoke.end."); return "return value: As

1. std::p romise can be used to provide data transfer between threads.std::future = std::p romise.get_future ().Promise can be assigned to a thread in std::p romise.set_value.After the assignment, Std::future.get () returns the value set in the other thread.#include#include#includestd::p romiseint>promis;intMainintargcConst Char*argv[]) {Std::futureint> Furesult =promis.get_future (); Std::thread T ([] () {std::this_thread::sleep_for (Std::chrono::seconds (Ten)); Promis.set_value (123); });

Consider the following code:#include #includestring>#include#include#includeStd::mutex m;std::condition_variable cv;std::stringdata;BOOLReady =false;intresult =0; voiddo_work () {std::this_thread::sleep_for (Std::chrono::seconds (1)); Result=123; {Std::lock_guardLK (m); Ready=true; } cv.notify_one ();} intMain () {Std::thread thread (do_work); Thread.detach (); Std::unique_lockLK (m); Cv.wait (LK, []{returnReady ;}); Std::cout"result="'\ n';}C+

("Step2 current ThreadID" + Thread.CurrentThread.ManagedThreadId); }We can see that Step2 is very simple, there is no delay, is to output a paragraph on the screen, and Step1 is more complicated, it is an asynchronous method, and use Task.run to open two new threads, and the firstThe running time of a thread is 3 seconds, very long, haha, the second one is to output a paragraph on the screen! Now what happens when we write Step1 and Step2 together?var New threadtest (); test. Step1 ();

Once, we may have used thread. When the main thread is running. A new thread is opened to run the new method.Today to see someone sent me a piece of code to find a not know the await, but also feel very familiar with the look, feel is the thread that the thing, check the next, found a simple way to realize multi-threaded asynchronous programming.(Ps:framework at 4.5 or more talent enough oh ~)。 Console.WriteLine ("Exit Async Method");

Async and await are introduced in C # 5.0. These two keywords will make it easier for you to write asynchronous code. Look at an example: public class MyClass {public MyClass () { displayvalue ();//There's no blocking here. System.Diagnostics.Debug.WriteLine ("MyClass () end."); } Public task An asynchronous Method Displayvalue () that async keyword ta

The async/await of. NET 4.5 is really a magic thing. It's so clever that I can't help but wonder about its implementation, but it's hard to get a glimpse of its path. Unexpectedly, I read this article Asynchronous Programming in C # using Iterators, which is like a crash. Meiyu did not dare to exclusive, so I wrote this article to share some of my thoughts with them, and I will give them some valuable insig

example: "218.108.242.108" strarea_ip[1] IP address region information String No for example: "Hangzhou, Zhejiang" The following is the IP parameter that is passed in to obtain the region to which it belongs: According to the third party website (WebService provider), to obtain the IP address of the client by crawling the Internet IP address of the computer on this website.Of course, if that day this site changed the domain name or does not exist, this method will not be used properly Oh!The

an array that contains IP information String [] Whether For example: count=2, which indicates an array length of 2 (0,1) STRAREA_IP[0] IP address requested by the client String Whether For example: "218.108.242.108" STRAREA_IP[1] IP Address Region information String Whether For example: "Hangzhou, Zhejiang" The following is the IP parameter passed in to obtain the o