| This directory contains the C# Protocol Buffers runtime library. | |
| Usage | |
| ===== | |
| The easiest way how to use C# protobufs is via the `Google.Protobuf` | |
| NuGet package. Just add the NuGet package to your VS project. | |
| You will also want to install the `Google.Protobuf.Tools` NuGet package, which | |
| contains precompiled version of `protoc.exe` and a copy of well known `.proto` | |
| files under the package's `tools` directory. | |
| To generate C# files from your `.proto` files, invoke `protoc` with the | |
| `--csharp_out` option. | |
| Supported platforms | |
| =================== | |
| The runtime library is built as a class library, supporting targets of: | |
| - .NET 4.5+ (`net45`) | |
| - .NET Standard 1.1 and 2.0 (`netstandard1.1` and `netstandard2.0`) | |
| - .NET 5+ (`net50`) | |
| You should be able to use Protocol Buffers in Visual Studio 2012 and | |
| all later versions. This includes all code generated by `protoc`, | |
| which only uses features from C# 3 and earlier. When compiling generated | |
| code with old compilers (before C# 7.2) you need to define the | |
| `GOOGLE_PROTOBUF_REFSTRUCT_COMPATIBILITY_MODE` symbol in your project | |
| so that the generated classes don't implement `IBufferMessage`, which uses | |
| `ref struct` types. | |
| Building | |
| ======== | |
| Open the `src/Google.Protobuf.sln` solution in Visual Studio 2022 or | |
| later. | |
| Although *users* of this project are only expected to have Visual | |
| Studio 2012 or later, *developers* of the library are required to | |
| have Visual Studio 2022 or later, as the library uses C# 10 features | |
| in its implementation and runs tests under .NET 6. These features | |
| have no impact when using the compiled code - they're only relevant | |
| when building the `Google.Protobuf` assembly. | |
| Testing | |
| ======= | |
| The unit tests use [NUnit 3](https://github.com/nunit/nunit). Tests can be | |
| run using the Visual Studio Test Explorer or `dotnet test`. | |
| .NET 3.5 | |
| ======== | |
| We don't support .NET 3.5. It *used* to be feasible to build this library | |
| targeting .NET 3.5, but a number of changes requiring newer runtime/framework | |
| features have been added over time. While it would no doubt be *possible* to | |
| rework the current implementation to allow most of the functionality to be built | |
| in .NET 3.5, this would create an undue maintenance burden. | |
| History of C# protobufs | |
| ======================= | |
| This subtree was originally imported from https://github.com/jskeet/protobuf-csharp-port | |
| and represents the latest development version of C# protobufs, that will now be developed | |
| and maintained by Google. All the development will be done in open, under this repository | |
| (https://github.com/protocolbuffers/protobuf). | |
| The previous project differs from this project in a number of ways: | |
| - The old code only supported proto2; the new code initially only supported | |
| proto3 (so no unknown fields, no required/optional distinction, no | |
| extensions); since then proto2 support has been added | |
| - The old code was based on immutable message types and builders for | |
| them | |
| - The old code did not support maps or `oneof` | |
| - The old code had its own JSON representation, whereas the new code | |
| uses the standard protobuf JSON representation | |
| - The old code had no notion of the "well-known types" which have | |
| special support in the new code | |
| - The old project supported some older platforms (such as older | |
| versions of Silverlight) which are not currently supported in the | |
| new project |