This directory contains the C# Protocol Buffers runtime library.
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.
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
andnetstandard2.0
) - .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.
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.
The unit tests use NUnit 3. Tests can be
run using the Visual Studio Test Explorer or dotnet test
.
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.
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