SnakeCaseJson

References and Related Articles

Custom Naming Policy for JSON in C# - Code Maze

New Features in .NET 8 JSON Naming Policy

As of the writing of this article, Microsoft released .NET 8 which adds new, popular naming conventions to the JsonNamingPolicy class. If we look at the Microsoft documentation we see we have five static properties:

• CamelCase provides a “camelCase” policy (in .NET Core 3.0 and higher)
• KebabCaseLower provides a “kebab-case-lower” policy (new in .NET 8)
• KebabCaseUpper provides a “Kebab-Case-Upper” policy (new in .NET 8)
• SnakeCaseLower provides a “snake_case_lower” policy (new in .NET 8)
• SnakeCaseUpper provides a “Snake_Case_Upper” policy (new in .NET 8)

The kebab cases use a dash (-) between words and have upper- and lowercase variations, whereas the snake cases use an underscore (_) between words and also have upper- and lowercase variations.

Since these are static properties we can assign them directly to the PropertyNamingPolicy property:

var snakeCaseLowerPolicy = new JsonSerializerOptions
{
  PropertyNamingPolicy = JsonNamingPolicy.SnakeCaseLower
};

If we use this with our person object from earlier, we see the properties formatted as snake-case:

{ "given_name": "Name1", "sur_name": "Surname1" }

JsonNamingPolicy Class (System.Text.Json) | Microsoft Learn

Naming Policy	Description
CamelCase	Gets the naming policy for camel-casing.
KebabCaseLower	Gets the naming policy for lowercase kebab-casing.
KebabCaseUpper	Gets the naming policy for uppercase kebab-casing.
SnakeCaseLower	Gets the naming policy for lowercase snake-casing.
SnakeCaseUpper	Gets the naming policy for uppercase snake-casing.

System.Text.Json snakecase :: michaelrose.dev — Michael's blog

Snake-casing JSON requests and responses with ASP.NET Core and System.Text.Json | CodeBork Tales from the Codeface

C# - Deserialize JSON using different property names | makolyte

When JSON property names and class property names are different, and you can’t just change the names to match, you have three options:

• Use the JsonPropertyName attribute.
• Use a naming policy (built-in or custom).
• A combination of these two. In other words, use JsonPropertyName for special cases that your naming policy doesn’t handle.

These options affect both deserialization and serialization.

Let’s say you have the following JSON with camel-cased property names:

{
  "title": "Code",
  "subtitle": "The Hidden Language of Computer Hardware and Software",
  "authorName": "Charles Petzold",
  "dateFirstPublished": "2000-10-11T00:00:00"
}

Here’s an example of using the JsonPropertyName attribute:

using System.Text.Json.Serialization;

public class Book
{
    [JsonPropertyName("title")]
    public string Title { get; set; }

    [JsonPropertyName("subtitle")] 
    public string Subtitle { get; set; } 

    [JsonPropertyName("authorName")] 
    public string AuthorName { get; set; } 

    [JsonPropertyName("dateFirstPublished")] 
    public DateTime DateFirstPublished { get; set; }
}

Note: The Newtonsoft equivalent is [JsonProperty(“title”)]