Paste JSON as C#

A simple and fast VS Code extension to paste JSON from your clipboard as C# classes or records.

Perfect for quickly converting JSON from REST API documentation into C# request/response objects.

Features

Context Menu Integration: Right-click in any .cs file to see "Paste JSON as C#"
JSON Validation: Validates clipboard content before conversion with helpful error messages
Configurable Root Class Name: Choose to always use a default name or be prompted each time
Type Styles: Generate classes, positional records, or records with properties
Collection Types: Choose between Array, List, IList, IEnumerable, or IReadOnlyList
Nullable Support: Handle nullable reference types with annotations or default values
Namespace Detection: Optionally include file-scoped namespace from .csproj structure
Serialization Attributes: Optionally add [JsonPropertyName] (System.Text.Json) or [JsonProperty] (Newtonsoft.Json) when JSON keys differ from C# names
Instant Rename: Root class name is selected as a linked placeholder after paste — just start typing to rename all occurrences at once

Usage

Copy JSON to your clipboard
Open a .cs file in VS Code
Right-click where you want to insert the code
Select "Paste JSON as C#"
Enter a root class name (or use the default)
If you kept the default name, it's highlighted — just type to rename all occurrences instantly

Example

Input JSON:

{
  "id": 123,
  "name": "John Doe",
  "email": "john@example.com",
  "roles": ["admin", "user"],
  "address": {
    "street": "123 Main St",
    "city": "New York"
  }
}

Output C#:

public class Root
{
    public long Id { get; set; }
    public string Name { get; set; }
    public string Email { get; set; }
    public IEnumerable<string> Roles { get; set; }
    public Address Address { get; set; }
}

public class Address
{
    public string Street { get; set; }
    public string City { get; set; }
}

Extension Settings

Setting	Default	Description
`json2csharp.alwaysUseRootClassName`	`false`	Skip the prompt and always use the default root class name
`json2csharp.rootClassName`	`"Root"`	Default root class name
`json2csharp.typeStyle`	`"class"`	Type style: class, recordPositional, or recordProperties
`json2csharp.collectionType`	`"IEnumerable"`	Collection type: Array, List, IList, IEnumerable, IReadOnlyList
`json2csharp.nullableReferenceTypes`	`"none"`	Nullable handling: none, nullable (?), or defaultValues
`json2csharp.inferEnums`	`false`	Attempt to infer enum types from JSON values
`json2csharp.inferDateTimes`	`true`	Attempt to infer DateTime types from strings
`json2csharp.namespaceMode`	`"withoutNamespace"`	Namespace inclusion: `withoutNamespace` (single menu, no namespace), `withNamespace` (single menu, always namespace), or `choose` (submenu with both options)
`json2csharp.serializationAttributes`	`"SystemTextJson"`	Serialization attributes: none, SystemTextJson, or NewtonsoftJson
`json2csharp.attributeRendering`	`"whenDifferent"`	When to render attributes: whenDifferent or always. Only applies when serializationAttributes is SystemTextJson or NewtonsoftJson

Requirements

VS Code 1.96.0 or later

Known Issues

Complex union types may not convert perfectly
Very large JSON files may take a moment to process

License

MIT

json2csharp

Gasrulle