How to have an auto incrementing version number (Visual Studio)?

Question

I want to store a set of integers that get auto incremented at build time:

int MajorVersion = 0;
int MinorVersion = 1;
int Revision = 92;

When I compile, it would auto-increment Revision. When I build the setup project, it would increment MinorVersion (I'm OK with doing this manually). MajorVersion would only be incremented manually.

Then I could display a version number in menu Help/About to the user as:

  Version: 0.1.92

How can this be achieved?

This question asks not only how to have an auto-incrementing version number, but also how to use that in code which is a more complete answer than others.

Answer 1

If you add an AssemblyInfo class to your project and amend the AssemblyVersion attribute to end with an asterisk, for example:

[assembly: AssemblyVersion("2.10.*")]

Visual studio will increment the final number for you according to these rules (thanks galets, I had that completely wrong!)

To reference this version in code, so you can display it to the user, you use reflection. For example,

Version version = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version;
DateTime buildDate = new DateTime(2000, 1, 1)
                        .AddDays(version.Build).AddSeconds(version.Revision * 2);
string displayableVersion = $"{version} ({buildDate})";

Three important gotchas that you should know

From @ashes999:

It's also worth noting that if both AssemblyVersion and AssemblyFileVersion are specified, you won't see this on your .exe.

From @BrainSlugs83:

Setting only the 4th number to be * can be bad, as the version won't always increment. The 3rd number is the number of days since the year 2000, and the 4th number is the number of seconds since midnight (divided by 2) [IT IS NOT RANDOM]. So if you built the solution late in a day one day, and early in a day the next day, the later build would have an earlier version number. I recommend always using X.Y.* instead of X.Y.Z.* because your version number will ALWAYS increase this way.

Newer versions of Visual Studio give this error:

(this thread begun in 2009)

The specified version string contains wildcards, which are not compatible with determinism. Either remove wildcards from the version string, or disable determinism for this compilation.

See this SO answer which explains how to remove determinism (https://stackoverflow.com/a/58101474/1555612)