Creating objects using an older version of Google Protobuf

Question

I was originally using Google Protobuf 3.1 protoc compiler to auto-generate a Filepath.cs class. Because the filepath.proto file was written for proto2 syntax, I had to manually change the file to comform to proto3.

It turns out that I need to stick with the proto2 syntax for reasons outside of my control. I've found out that protoc version 3.0.0alpha3 supports C# code-generation for proto2 files (newer protoc versions do not support c# code generation for proto2 files which is why I reverted to alpha 3).

The generated code is different and my preexisting code (that originally worked with protoc 3.1, no longer works):

    FilePath fp = new FilePath
    {
        Path = "TestPath",
        TestValue = 5.0f
    };  

This chunk of code no longer works with the alpha3 generated files. Does anyone know how to properly serialize/deserialize an object using older versions of Protobuf, or if the older tutorials are archived somewhere?

I am able to do:

FilePath fp; 
fp.Path = "test_path_here"; //ERROR - no SETTER, only a GETTER

The fields Path and TestValue only have getters, no setters.

Answer 1

Figured it out by going to an older version of the Protobufs project on github. I found a java example that led me to figuring out how to create a new object in C#. Take a look at this 3.0.x source and you should be able to figure it out: https://github.com/google/protobuf/blob/3.0.x/examples/AddPerson.java

This is what I ended up with:

    FilePath.Builder fp = FilePath.CreateBuilder();
    fp.SetPath("TestPath");
    fp.SetTestValue(7.0f);