ConfigureAwait(false) vs setting sync context to null

I often see recommended for async library code, that we should use `ConfigureAwait(false)` on all async calls to avoid situations where the return of our call will be scheduled on a UI thread or a web...

23 Jan at 21:56

Xamarin.Forms.Navigation.PopAsync() Does Not Pop Page

In Xamarin.Forms, when we use `Navigation.PopAsync()`, the page does not pop in iOS. After `PopAsync()` the same page remains.

24 Apr at 16:47

Filtering a pyspark dataframe using isin by exclusion

I am trying to get all rows within a dataframe where a columns value is not within a list (so filtering by exclusion). As an example: ``` df = sqlContext.createDataFrame([('1','a'),('2','b'),('3','b...

What does purple underlines mean in visual studio editor?

I am facing some purple (or violet?) underlines in Visual Studio 2015 today, something I have never seen before. [](https://i.stack.imgur.com/gUqNc.jpg) I held the cursor over the text but nothing h...

21 Jan at 03:18

Project not build in active configuration Visual Studio MacOS .net Core

I have created an Console Application(.Net Core) in Visual Studios MacOS Preview. In the project solution I don't see my program.cs also other things are not available it says [](https://i.stack.img...

Access to configuration without dependency injection

I was wondering if there was a way to access Configuration (Microsoft.Extensions.Configuration) without the use of dependency injection. Only examples I see are through constructor injection (using I...

20 Jan at 20:38

Initialize a Map containing arrays in TypeScript

I want to make a `Map` where each member contains an array of strings. But how do I initialize and type it (in a single statement)? (naively) I tried this: ``` private _gridOptions:Map<string, Array<s...

1 Oct at 16:13

ServiceStack OrmLite - Is it possible to do a group by and have a reference to a list of the non-grouped fields?

It may be I'm still thinking in the Linq2Sql mode, but I'm having a hard time translating this to OrmLite. I have a customers table and a loyalty card table. I want to get a list of customers and f...

20 Jan at 16:55

How to implement the repository pattern the right way?

When implementing the repository pattern for my ASP.NET project, I encountered some problems on which I can't get my head around. So I have a few questions on how to implement the repository pattern t...

How to merge two lists and remove duplicates

Given I have two list like the following: ```csharp var listA = new List { "test1", "test2", "test3" }; var listB = new List { "test2", "test3", "test4" }; ``` I want a third list with: ``...

2 May at 13:1

nginx: [emerg] "server" directive is not allowed here

I have reconfigured nginx but i can't get it to restart using the following config: conf: ``` server { listen 80; server_name www.example.com; return 301 $scheme://example.com$request_uri; } ...

15 Dec at 08:18

What does the win/any runtime mean in .NET Core

I'm building a C# .NET core application and it is targeting the `net452` framework. When I publish I can specify a runtime (--runtime), if I don't specify any runtime it uses `win7-x64` (I assume tha...

28 Nov at 05:53

Amazon S3 console: download multiple files at once

When I log to my I am unable to download multiple selected files (the WebUI allows downloads only when one file is selected): [https://console.aws.amazon.com/s3](https://console.aws.amazon.com/s3) ...

20 Jan at 13:27

Visual Studio 2017: "Object reference not set to an instance of an object" while loading the project

I have a project inside the VS solution that loads correctly in VS2015, but it seems to be corrupted in VS2017 (RC2). In the solution explorer it shows that its "load failed" and when I try to reload...

How to convert result table to JSON array in MySQL

I'd like to convert result table to JSON array in MySQL using preferably only plain MySQL commands. For example with query ``` SELECT name, phone FROM person; | name | phone | | Jack | 12345 | | Joh...

20 Jun at 22:25

How to do String.Copy in .net core?

In porting a .net framework app to .net core app, there are some uses of [String.Copy](https://msdn.microsoft.com/en-us/library/system.string.copy(v=vs.110).aspx) to copy strings. But it looks this me...

20 Jan at 07:48

Show only selected controllers in swagger-swashbuckle UI

I am currently using swagger in my project and i have more than 100 controllers there. I guess due to the large number of controller, swagger UI documentation page takes more than 5 min to load its c...

20 Jan at 07:7

Use SQL LIKE operator in C# LINQ

I am building up a query in C#. For integer and string fields, case is quite simple. For date fields, I am using following query: ``` list.Where("myDateColumn >= DateTime(2017,1,20)"); ``` How I ca...

20 Jan at 06:56

golang convert "type []string" to string

I see some people create a `for` loop and run through the slice as to create a string, is there an easier way to convert a `[]string` to a `string`? Will `sprintf` do it?

25 Sep at 10:5

What's the difference between Content and None when "Always copy to output directory" is set?

In csproj file, we can include a file using either `None` or `Content` element. From MSDN, it says that: > None - The file is not included in the project output group and is not compiled in the bui...

20 Jan at 01:25

Replacing a character from a certain index

How can I replace a character in a string from a certain index? For example, I want to get the middle character from a string, like abc, and if the character is not equal to the character the user spe...

31 May at 21:46

C# get value from deserialized json object

I'm currently Deserializing a json string using the Newtonsoft.Json nuget packet using the following code: ``` var data = (JObject)JsonConvert.DeserializeObject(json); ``` Now I'm receiving an obje...

20 Jan at 00:6

In ServiceStack how can i use an externally issued JWT

I'm working in c# on .net/mono on an IOT type project with devices and a cloud service. The cloud services handle authentication and claims using IdentityServer3 and I have it successfully providing a...

EF 6 - How to correctly perform parallel queries

When creating a report I have to execute 3 queries that involve separated entities of the same context. Because they are quite heavy ones I decided to use the `.ToListAsync();` in order to have them r...

19 Jan at 22:13

Google Protocol Buffers - serialize to byte array

I'm following the tutorial for using Google Protocol Buffers for C#. I don't see an example for converting an object into a byte array - does anyone know how to do that? I've auto-generated a FilePath...