Questions

Convert IAsyncEnumerable to List

So in C#8 we got the addition of the `IAsyncEnumerable` interface. If we have a normal `IEnumerable` we can make a `List` or pretty much any other collection we want out of it. Thanks to Linq there....

What is @context and why is it red?

I'm using the `BlazoredTypeahead` component in a blazor server side app and I'd like to know where the @context keyword is coming from. The following code runs fine, but VS is reporting that it Cannot...

16 May at 18:29

Does JsonStringEnumConverter (System.Text.Json) support null values?

I am shifting my code from .NET Core 2.x to .NET Core 3.x (i.e. use the native library `System.Text.Json`). In doing this, I ran into some issues with how the former `Newtonsoft.Json` support for null...

1 Jan at 15:50

C# 8 Using Declaration Scope Confusion

With the new C# 8 Using Declaration Syntax, what is containing scope of a second consecutive using statement? Previous to C# 8, having a consecutive using statement like: ``` using(var disposable ...

How to install Nuget package using windows command line in C# project?

I have downloaded NuGet version - 5.1.0 and tried to install one of the package - log4net using cmd. it failed. below is error - > Microsoft Windows [Version 10.0.19042.1348] (c) Microsoft Corporat...

How to use System.HashCode.Combine with more than 8 values?

.NET Standard 2.1 / .NET Core 3 [introduce](https://github.com/dotnet/corefx/issues/14354) [System.HashCode](https://learn.microsoft.com/en-us/dotnet/api/system.hashcode) to quickly combine fields and...

17 Dec at 13:18

Visual Studio unable to run .NET Core tests

Using the latest version of Visual Studio, I'm unable to run any tests in the tests explorer. The error message in the `Tests` output window is: ``` Testhost process exited with error: It was not pos...

Is this pattern matching expression equivalent to not null

I stumbled upon [this code](https://github.com/devmentors/Nanoservice/blob/37f5e3afee84dabefad654495ea0839e90032200/src/Sidecar/Program.cs#L71) on github: ``` if (requestHeaders is {}) ``` and I do...

16 Dec at 17:17

Publish Single File (Release) fails for WPF .NET Core 3.1 application

I'm trying to publish a WPF Application (to a folder) targeting .NET Core 3.1, using Publish Single File, targeting win-x86. The application publishes fine for Debug, but fails for Release. If I desel...

How to Upload File from Angular to ASP.NET Core Web API

Similar questions have been asked but after looking through all of those and many blog posts on the subject I have not been able to figure this out so please forgive me. I am creating a simple blog w...

Equivalent of UseUrls for .NET Core IHostBuilder

Previously, with .NET Core, I could add `UseUrls` to my `Program.cs` file to set the URL that the web server would run on: However, in .NET Core 3.1, the default format of `Program.cs` changed: I trie...

6 May at 05:43

No handles with labels found to put in legend

I'm trying to create a parallelogram in PyPlot. I'm not up to drawing the parallelogram--first I'm putting in the vector arrows--using the following code: ``` fig = plt.figure() ax = fig.add_subplot(1...

12 Jul at 17:52

Error occurred while access Microsoft.Extensions.HostingServices. Could not parse JSON file

I was trying to create a migration for an MVC ASP.NET Core 3.10 project using Visual Studio 2019. I got two errors: 1. An error occurred while accessing the Microsoft.Extensions.Hosting services. Co...

Problem with EF OrderBy after migration to .net core 3.1

Consider this code: ``` _dbContext.Messages .GroupBy(m => new { MinId = m.SenderId <= m.RecipientId ? m.SenderId : m.RecipientId, MaxId = m.SenderId > m.RecipientI...

Message: Trying to access array offset on value of type null

I'm getting this error on multiple occasion in a script (invoiceplane) I have been using for a few years now but which hasn't been maintained unfortunately by its creators: ``` Message: Trying to acc...

14 Dec at 16:29

Error when trying to run code: Debugger operation failed, Native error= Cannot find the specified file

I recently completely transitioned to Linux but struggle to find a good way to code in C#. I discovered Monodevelop which looks similar to Visual Studio, but whenever I try to run any code I get this ...

30 Aug at 09:31

Xamarin & IIS LocalHost WebApi gives error - System.Net.Http.HttpRequestException: 'Network subsystem is down'

I have 2 Applications here. One is a Xamarin Application and the other is a Asp.Net MVC Application which has the WebApi to connect to a SqlServer Database "where the database is on a Hosted Website o...

14 Dec at 11:24

How use Microsoft.Extensions.Logging from Library code?

I have a hard time understanding what is the best way to use Microsoft.Extensions.Logging in a general library. with NLog you can do: ``` public class MyClass { private static readonly NLog.Logger...

10 Jul at 19:8

Error while validating the service descriptor 'ServiceType: INewsRepository Lifetime: Singleton ImplementationType: NewsRepository':

I try get data from my database with repository Pattern i have 3 project > Bmu.Mode 'this is for model to create database'Bmu.Repo 'it have 2 folder for repository include contract/InewsRepository....

CorsAuthorizationFilterFactory in asp.net core 3

I am trying to migrate a project from asp.net Core 2.2.6 to asp.net core 3.0 In my startup I had ``` services.AddMvc(options => { options.Filters.Add(new CorsAuthorizationFilterFactory("default")...

Command to clear all breakpoints in VSCode (as in visual studio)

In visual studio you can `Ctrl+Shit+F9` to clear all breakpoints. Is there a similar function in VsCode? I couldn't find any good answer. Thanks!

13 Dec at 14:16

C#.net Web Request could not get 404 custom error message while calling web API but postman does

I am calling external Web API in my own Web API using ServiceStack. For the unsubscribed user, external web API throws expected "404 Not found" exception with the custom message as . I can see it in...

How to get the digits before some particular word using regex in c#?

We will use below regex to get the digits before the words. Example : > 838123 someWord 8 someWord 12 someWord `(\d+)\s*someWord` But sometimes anything will come between Number and word.Ple...

2 May at 11:1

Deserialize anonymous type with System.Text.Json

I am updating some apps for .NET Core 3.x, and as part of that I'm trying to move from `Json.NET` to the new `System.Text.Json` classes. With Json.NET, I could deserialize an anonymous type like so: ...

Why does this code give a "Possible null reference return" compiler warning?

Consider the following code: ``` using System; #nullable enable namespace Demo { public sealed class TestClass { public string Test() { bool isNull = _test == nu...

12 Dec at 15:26