C# target manual

The C# target turns checked TypeScript into C# source. It can also create a normal SDK-style project for that source.

First C# application

import { Console } from "@tsonic/dotnet/System.js";
import { List } from "@tsonic/dotnet/System.Collections.Generic.js";
import type { int } from "@tsonic/csharp/types.js";

export function run(): int {
  const values = new List<int>();
  values.Add(42);
  Console.WriteLine(values.Count);
  return values.Count;
}

run();

The entry module runs from top to bottom. An exported function named main is not special; call the function if it should run.

The @tsonic/dotnet/* imports are virtual source modules built from .NET metadata. TypeScript checking selects a source overload. The C# target then uses the provider’s exact identity to select the CLR member.

Use surfaces: ["js"] when the program needs JavaScript globals and built-ins. Install @tsonic/csharp-nodejs when it imports node:*. Those are independent choices.

C# target manual

First C# application

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