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There are two ways to serialize an object’s properties to JSON in alphabetical order using System.Text.Json: I’ll show how to do these two options below. Option 1 – Manually alphabetize with JsonPropertyOrder You can specify the exact serialization ordering by using the JsonPropertyOrder attribute. Therefore, to serialize in alphabetical order, first arrange the properties in … Read more
I wrote about how to add custom validation attributes. These are used for model validation on the server-side. You can also use these for client-side validation, which I’ll show in this article. 1 – Implement IClientModelValidator The first step is to implement the IClientModelValidator interface in the custom validation attribute class. This has a single … Read more
Input formatters are used to deserialize the request body to a model object (which is then passed into an action method). There are built-in input formatters for handling JSON and XML. You can add your own input formatter when you want to customize request body deserialization. There are two scenarios where a custom InputFormatter would … Read more
When you use HttpClient to make requests, you can directly get the status code from the HttpResponseMessage object, like this: The main reason for checking the status code is to determine if the request was successful and then reacting to error status codes (usually by throwing an exception). The HttpResponseMessage class has two helpers that … Read more
When you use reflection to get properties, you can get just the subclass properties by using BindingFlags.DeclaredOnly (this causes it to exclude inherited properties). Here’s an example: Note: Use GetType() if you have an object. Use typeof() if you have a class. The code outputs just the subclass properties (from the Driver subclass): Get base … Read more
When your class has multiple constructors, you can use the JsonConstructor attribute to specify which constructor to use during deserialization. Here’s an example. The Person class has two constructors. I put the JsonConstructor attribute on one of the constructors: Note: JsonConstructor for System.Text.Json was added in .NET 5. Now deserialize a JSON string to the … Read more
The simplest way to deserialize JSON to a derived type is to put the type name in the JSON string. Then during deserialization, match the type name property against a set of known derived types and deserialize to the target type. System.Text.Json doesn’t have this functionality out of the box. That’s because there’s a known … Read more
You can use the JsonPropertyOrder attribute to control the order that properties get serialized. You specify the order as an integer, and it serializes the properties in ascending order. Here’s an example: Note: Properties have a default order value of 0. Now serialize an object to JSON: This generates the following JSON: Notice the properties … Read more
There are two ways to do inheritance mapping in EF Core: Let’s say we have a database with employees. All employees have an id and a name. There are currently two types of employees: programmers and drivers. Programmers have a language (ex: C#), and drivers have a car (ex: Honda). We can model this with … Read more
EF Core has built-in retry functionality. To use it, you can call options.EnableRetryOnFailure(), like this: The retry logic is contained in execution strategy classes. The above code is using the default execution strategy class (SqlServerRetryingExecutionStrategy). When you execute a query, it goes through the execution strategy class. It executes the query and checks for transient … Read more
To create a custom exception, create a subclass of the Exception class, like this: Then throw it just like you would any other exception, like this: It’s a good idea to call the base constructor from your constructor and pass in your custom error message. If this exception is unhandled, or if you are logging … Read more
You can use a hosted BackgroundService in ASP.NET Core for two purposes: In this article, I’ll show how to create and register a hosted BackgroundService. In this example, it periodically pings a URL and logs the results. 1 – Subclass BackgroundService The first step is to subclass BackgroundService: In this example, we’ll create a background … Read more
The Switch Statement code smell refers to using switch statements with a type code to get different behavior or data instead of using subclasses and polymorphism. In general, it looks like this: This switch(typeCode) structure is typically spread throughout many methods. This makes the code difficult to extend, and violates the Open-Closed Principle. This principle … Read more