In this post I described the problem that by default, DataAnnotation validation doesn't recursively inspect all properties in an object for DataAnnotation attributes. There are several solutions to this problem, but in this post I used the MiniValidation library from Damian Edwards. This simple library provides a convenience wrapper around DataAnnotation validation, as well as providing features like recursive validation. Finally I showed how you can replace the built-in DataAnnotation validation with a MiniValidation-based validator

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddOptions<MySettings>()
    .BindConfiguration("MySettings")
    .ValidateMiniValidation() // 👈 Replace with mini validation
    .ValidateOnStart();

var app = builder.Build();

OptionsValidationException: 
  DataAnnotation validation failed for 'MySettings' member: 'Nested.Value' with errors: 'The Value field is required.'.; 
  DataAnnotation validation failed for 'MySettings' member: 'Nested.Count' with errors: 'The field Count must be between 1 and 100.'.
Microsoft.Extensions.Options.OptionsFactory<TOptions>.Create(string name)
Microsoft.Extensions.Options.OptionsMonitor<TOptions>+<>c__DisplayClass10_0.<Get>b__0()

Entity Framework Core 2.0 introduces global query filters that can be applied to entities when a model is created. It makes it easier to build multi-tenant applications and support soft deleting of entities. This blog post gives a deeper overview of how to use global query filters in real-life applications and how to apply global query filters to domain entities automatically. 

Some NewSQL solutions

NewSQL-db-logosVoltDB  (in-memory database) : http://voltdb.com

ClustrixDB (distributed peer-to-peer SQL database) : http://www.clustrix.com

NuoDB (distributed database management) : http://www.nuodb.com

GenieDB (based on MySQL) : http://www.geniedb.com

ScaleArc (SQL traffic manager ) :  http://www.scalearc.com

ScaleDB (MySQL scalability) : http://scaledb.com

Tokutek/TokuDB (MySQL/MariaDB scallability): http://www.tokutek.com

JustoneDB (built upon PostgreSQL) : http://www.justonedb.com

MemSQL (in-memory database) : http://www.memsql.com   

At Microsoft Build 2021 .NET MAUI Preview 4 was launched. This version is already pretty complete and starts to reflect what the end result is going to look like. In this video I will show you the new .NET MAUI template in Visual Studio 2019 and walk you through the Weather 21 demo app.  

In this video Anders Hejlsberg spends some time discussing TypeScript. He starts with the reasons behind creating TypeScript (the so called elevator speech) and then moves on to some of the features coming in the next release. He mentions a number of features but spends the time discussing the null (and corresponding undefined) types and how TypeScript 2 makes handling them much easier. 

In this series I answer various .NET questions. Some of them are asked during interviews, some of them I see on the internet, some of them are completely made up. The goal is to provide short answer with links to references if needed. This is by no means a .NET tutorial or experts reference, this is just a bunch of useful answers to refresh your knowledge. 

This ebook is no fluff–just a developer-to-developer breakdown of what’s in store for .NET in 2015. Included are code snippets and step-by-step tutorials on handy new features and techniques.