async-await

问题 I was hoping somebody could enlighten me a little bit on an issue I am facing in regards to async/await exception handling with HttpClient. I have written some code to illustrate, and it is being excecuted on both a Windows Phone 8 device and the emulator: private async void SearchButton_Click(object sender, EventArgs e) { try { HttpClient client = new HttpClient(); System.Diagnostics.Debug.WriteLine("BEGIN FAULTY REQUEST:"); string response = await client.GetStringAsync("http://www

问题 I'm trying to detect during runtime if the source code of a method of a class has been changed. Basically I retrieve the method body (IL), hash it with md5 and store it in the database. Next time I check the method, I can compare the hashes. public class Changed { public string SomeValue { get; set; } public string GetSomeValue() { return SomeValue + "add something"; } public async Task<string> GetSomeValueAsync() { return await Task.FromResult(SomeValue + "add something"); } } I'm using Mono

问题 I'm trying to upload a file into S3bucket using with AWS Sdk for .Net. I'm uploading a file like below: Private Async Sub Button1_Click(sender As Object, e As EventArgs) Handles Button2.Click Await AddFileToFolderAsync(file, bucketName, fld) ' here file is file's fullpath,buckatename is ' available s3bucket name, ' fld is target folder path into that s3bucket. End Sub Public Async Function AddFileToFolderAsync(FileName As String, bucketName As String, folderName() As String) As Task Try If

问题 Why I get a CORS error: Access to script at 'https://maps.googleapis.com/maps/api/js' from origin 'null' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. When I try to import dynamically Google Maps API in my JavaScript : await import('https://maps.googleapis.com/maps/api/js') But not when I do it in my HTML : <script defer src="https://maps.googleapis.com/maps/api/js"></script> Any idea would be really appreciate it. Note : if I

问题 I am re-writing my website and am trying to import my members from array of JSON objects. Each object represents a band that the user has uploaded. So I wrote a quick file that works with the list and my new database / authentication system, auth0. As outline in the comments below... First I Request an access token so I can create an account for each member using Auth0. Then I iterate through my array of objects representing bands. For each band object I have the code do a few things... First

问题 I'm having trouble understanding how to properly write middleware in Express that utilizes async/await, but doesn't leave a Promise floating in the ether after it's execution. I've read a ton of blogs and StackOverflow posts, and it seems like there is some consensus around using the following pattern in async/await middleware: const asyncHandler = fn => (req, res, next) => Promise .resolve(fn(req, res, next)) .catch(next) app.use(asyncHandler(async (req, res, next) => { req.user = await User

问题 I am working with mongodb and nodejs. I have an array of customers I have to create each inside database. const promises2 = customers.map(async customer => { if (!customer.customerId) { const counter = await Counter.findOne({ type: "Customer" }); console.log({counter}); const payload = { customerId: counter.sequence_value, }; await Customer.create(payload); await Counter.findOneAndUpdate({ type: "Customer" }, { $inc: { sequence_value: 1 } }); } }); await Promise.all([...promises2]); The issue

问题 I have some asynchronous operations that consist of two distinct stages. Initially I want to await them until the completion of their first stage, and later await them until their final completion. Here is a simplified version of these operations: async Task<string> TwoStagesAsync() { Console.WriteLine($"Stage 1 Started"); await Task.Delay(1000); // Simulate an I/O operation bool resultOfStage1 = true; Console.WriteLine($"Stage 1 Finished"); if (!resultOfStage1) return null; /* Stage

问题 I have some asynchronous operations that consist of two distinct stages. Initially I want to await them until the completion of their first stage, and later await them until their final completion. Here is a simplified version of these operations: async Task<string> TwoStagesAsync() { Console.WriteLine($"Stage 1 Started"); await Task.Delay(1000); // Simulate an I/O operation bool resultOfStage1 = true; Console.WriteLine($"Stage 1 Finished"); if (!resultOfStage1) return null; /* Stage

问题 I have firestore data somewhat like this: "Support": { "userid":"abcdxyz", "message": "hello" } I am using nodejs to fetch my data and I also want to show the email address and name of the person who sent this message. So I am using following function: database.collection("support").get().then(async function (collections) { var data = []; console.log("data collected"); collections.forEach(async function (collection) { var temp = {}; var collectionData = collection.data() var userInfo = await