Blazor

An experimental web UI framework using C#/Razor and HTML, running in the browser via WebAssembly

Blazor is a .NET web framework that runs in any browser. You author Blazor apps using C#/Razor and HTML.

Blazor uses only the latest web standards. No plugins or transpilation needed. It runs in the browser on a real .NET runtime (Mono) implemented in WebAssembly that executes normal .NET assemblies. It works in older browsers too by falling back to an asm.js based .NET runtime.

Blazor will have all the features of a modern web framework, including:

A component model for building composable UI
Routing
Layouts
Forms and validation
Dependency injection
JavaScript interop
Live reloading in the browser during development
Server-side rendering
Full .NET debugging both in browsers and in the IDE
Rich IntelliSense and tooling
Ability to run on older (non-WebAssembly) browsers via asm.js
Publishing and app size trimming

Note: Blazor is an experimental project. It's not (yet) a committed product. This is to allow time to fully investigate the technical issues associated with running .NET in the browser and to ensure we can build something that developers love and can be productive with. During this experimental phase, we expect to engage deeply with early Blazor adopters like you to hear your feedback and suggestions.

To see Blazor in action, check out Steve Sanderson's prototype demo at NDC Oslo last year. You can also try out a simple live Blazor app.

Getting Started

We are still very early in this project. There isn't yet anything you can download nor any project template you can use. Most of the planned features aren't implemented yet. Even the parts that are already implemented aren't yet optimized for minimal payload size. If you're keen, you can clone the repo, build it, and run the samples and tests.

Build

Prerequisites:

.NET Core SDK (>2.1.4)
Node.js (>8.3)

Run dotnet build from the solution directory.

Run tests

Run dotnet test test/<test name>.Test.csproj

Run end-to-end tests

Prerequisites:

Install selenium-standalone (requires Java 8 or later)
- npm install -g selenium-standalone
- selenium-standalone install
Chrome

Run selenium-standalone start

Run dotnet test test/<test name>.E2ETest.csproj

Contributing

There are lots of ways that you can contribute to Blazor! Read our contributing guide to learn about our development process and how to propose bug fixes and improvements.

Still got questions?

Check out our FAQ or open an issue.