async-await

Avoiding use of ActionBlock<TInput>.Post when PostDataflowBlockOptions.BoundedCapacity is not the default value?

由 允我心安 提交于 2020-05-30 08:13:09
问题 The bounty expires in 6 days . Answers to this question are eligible for a +100 reputation bounty. SpiritBob wants to reward an existing answer . I've heard that you can lose information if you use the Post method instead of the SendAsync method of an ActionBlock<T> object, when you decide to utilize it's BoundedCapacity property. Could someone please explain why that is so? 回答1: The Post method attempts to post an item synchronously and returns true or false , depending on whether the block

Avoiding use of ActionBlock<TInput>.Post when PostDataflowBlockOptions.BoundedCapacity is not the default value?

由 本小妞迷上赌 提交于 2020-05-30 08:13:07
问题 The bounty expires in 6 days . Answers to this question are eligible for a +100 reputation bounty. SpiritBob wants to reward an existing answer . I've heard that you can lose information if you use the Post method instead of the SendAsync method of an ActionBlock<T> object, when you decide to utilize it's BoundedCapacity property. Could someone please explain why that is so? 回答1: The Post method attempts to post an item synchronously and returns true or false , depending on whether the block

IIS worker thread vs web application thread

由 核能气质少年 提交于 2020-05-30 03:32:47
问题 I'm maintaining an ASP.NET Core web application that needs to repeatedly run some background threads. I know it's not a good design but currently I have to fix its major issues with minimum effort. Now I wonder if I should worry about handling users http requests by web server or not? Question is simple but I can't find any clear answer for it anywhere: What is the difference between threads that are created in application like this: Task.Run(() => { // some parallel job }) and worker threads

javascript async await Submitting a form with onsubmit using Promise

由 梦想的初衷 提交于 2020-05-30 03:22:26
问题 I'm having following code. <!DOCTYPE html> <html> <head> <script type="text/javascript"> function sleep( lf_ms ) { return new Promise( resolve => setTimeout( resolve, lf_ms ) ); } async function check_form() { alert( 'Test 1' ); await sleep( 1000 ); alert( 'Test 2' ); return false; } </script> </head> <body> <form name="myform" method="post" action="test.htm" onsubmit="return check_form();"> <input type="text" name="city"><br> <br> <a href="javascript:check_form();">check the method call via

Task.WaitAll keeps in loop

由 怎甘沉沦 提交于 2020-05-29 09:47:25
问题 I'm trying this async code just for testing the async keyword: public async Task<string> AsyncMethod() { var link = "http://www.google.com"; var webclient = new WebClient(); var result = await webclient.DownloadStringTaskAsync(new Uri(link)); return result; } public async Task<ActionResult> Index() { var a = AsyncMethod(); var b = AsyncMethod(); Task.WaitAll(a, b); return View(); } but when I debug it, the debugger hits the Task.WaitAll and just do nothing(the return keywork is never executed

Task.WaitAll keeps in loop

由 ≡放荡痞女 提交于 2020-05-29 09:47:05
问题 I'm trying this async code just for testing the async keyword: public async Task<string> AsyncMethod() { var link = "http://www.google.com"; var webclient = new WebClient(); var result = await webclient.DownloadStringTaskAsync(new Uri(link)); return result; } public async Task<ActionResult> Index() { var a = AsyncMethod(); var b = AsyncMethod(); Task.WaitAll(a, b); return View(); } but when I debug it, the debugger hits the Task.WaitAll and just do nothing(the return keywork is never executed

The trait `std::future::Future` is not implemented for `std::result::Result<reqwest::Response, reqwest::Error>`

由 北慕城南 提交于 2020-05-29 09:43:24
问题 I'm trying to run basic reqwest example: extern crate reqwest; extern crate tokio; #[tokio::main] async fn main() -> Result<(), reqwest::Error> { let res = reqwest::Client::new() .get("https://hyper.rs") .send() .await?; println!("Status: {}", res.status()); let body = res.text().await?; println!("Body:\n\n{}", body); Ok(()) } Error that I'm getting: --> src/main.rs:6:15 | 6 | let res = reqwest::Client::new() | _______________^ 7 | | .get("https://hyper.rs") 8 | | .send() 9 | | .await?; | |__

The trait `std::future::Future` is not implemented for `std::result::Result<reqwest::Response, reqwest::Error>`

由 烈酒焚心 提交于 2020-05-29 09:41:58
问题 I'm trying to run basic reqwest example: extern crate reqwest; extern crate tokio; #[tokio::main] async fn main() -> Result<(), reqwest::Error> { let res = reqwest::Client::new() .get("https://hyper.rs") .send() .await?; println!("Status: {}", res.status()); let body = res.text().await?; println!("Body:\n\n{}", body); Ok(()) } Error that I'm getting: --> src/main.rs:6:15 | 6 | let res = reqwest::Client::new() | _______________^ 7 | | .get("https://hyper.rs") 8 | | .send() 9 | | .await?; | |__

The trait `std::future::Future` is not implemented for `std::result::Result<reqwest::Response, reqwest::Error>`

由 我怕爱的太早我们不能终老 提交于 2020-05-29 09:41:20
问题 I'm trying to run basic reqwest example: extern crate reqwest; extern crate tokio; #[tokio::main] async fn main() -> Result<(), reqwest::Error> { let res = reqwest::Client::new() .get("https://hyper.rs") .send() .await?; println!("Status: {}", res.status()); let body = res.text().await?; println!("Body:\n\n{}", body); Ok(()) } Error that I'm getting: --> src/main.rs:6:15 | 6 | let res = reqwest::Client::new() | _______________^ 7 | | .get("https://hyper.rs") 8 | | .send() 9 | | .await?; | |__

SemaphoreSlim.WaitAsync before/after try block

由 不羁岁月 提交于 2020-05-28 13:46:48
问题 I know that in the sync world the first snippet is right, but what's about WaitAsync and async/await magic? Please give me some .net internals. await _semaphore.WaitAsync(); try { // todo } finally { _semaphore.Release(); } or try { await _semaphore.WaitAsync(); // todo } finally { _semaphore.Release(); } } 回答1: According to MSDN, SemaphoreSlim.WaitAsync may throw: ObjectDisposedException - If the semaphore has been disposed ArgumentOutOfRangeException - if you choose the overload which
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