Determine assembly version during a post-build event

This answer is a minor modification of the answer of Brent Arias. His PostBuildMacro worked quite well for me until a version update of Nuget.exe.

In the recent releases, Nuget trims non significant parts of the package version number in order to obtain a semantic version like "1.2.3". For example, the assembly version "1.2.3.0" is formatted by Nuget.exe "1.2.3". And "1.2.3.1" is formatted "1.2.3.1" as expected.

As I need to infer the exact package filename generated by Nuget.exe, I use now this adaptated macro (tested in VS2015):

<Target Name="PostBuildMacros">
  <GetAssemblyIdentity AssemblyFiles="$(TargetPath)">
    <Output TaskParameter="Assemblies" ItemName="Targets" />
  </GetAssemblyIdentity>
  <ItemGroup>
    <VersionNumber Include="$([System.Text.RegularExpressions.Regex]::Replace(&quot;%(Targets.Version)&quot;, &quot;^(.+?)(\.0+)$&quot;, &quot;$1&quot;))" />
  </ItemGroup>
</Target>
<PropertyGroup>
  <PostBuildEventDependsOn>
    $(PostBuildEventDependsOn);
    PostBuildMacros;
  </PostBuildEventDependsOn>    
  <PostBuildEvent>echo HELLO, THE ASSEMBLY VERSION IS: @(VersionNumber)</PostBuildEvent>
</PropertyGroup>

UPDATE 2017-05-24: I corrected the regex in this way: "1.2.0.0" will be translated to "1.2.0" and not "1.2" as previously coded.

---

And to answer to a comment of Ehryk Apr, you can adapt the regex to keep only some part of the version number. As an example to keep "Major.Minor", replace:

<VersionNumber Include="$([System.Text.RegularExpressions.Regex]::Replace(&quot;%(Targets.Version)&quot;, &quot;^(.+?)(\.0+)$&quot;, &quot;$1&quot;))" />

By

<VersionNumber Include="$([System.Text.RegularExpressions.Regex]::Replace(&quot;%(Targets.Version)&quot;, &quot;^([^\.]+)\.([^\.]+)(.*)$&quot;, &quot;$1.$2&quot;))" />

If (1) you don't want to download or create a custom executable that retrieves the assembly version and (2) you don't mind editing the Visual Studio project file, then there is a simple solution that allows you to use a macro which looks like this:

@(Targets->'%(Version)')

@(VersionNumber)

To accomplish this, unload your project. If the project somewhere defines a <PostBuildEvent> property, cut it from the project and save it elsewhere temporarily (notepad?). Then at the very end of the project, just before the end-tag, place this:

<Target Name="PostBuildMacros">
  <GetAssemblyIdentity AssemblyFiles="$(TargetPath)">
    <Output TaskParameter="Assemblies" ItemName="Targets" />
  </GetAssemblyIdentity>
  <ItemGroup>
    <VersionNumber Include="@(Targets->'%(Version)')"/>
  </ItemGroup>
</Target>
<PropertyGroup>
  <PostBuildEventDependsOn>
    $(PostBuildEventDependsOn);
    PostBuildMacros;
  </PostBuildEventDependsOn>    
  <PostBuildEvent>echo HELLO, THE ASSEMBLY VERSION IS: @(VersionNumber)</PostBuildEvent>
</PropertyGroup>

This snippet has an example <PostBuildEvent> already in it. No worries, you can reset it to your real post-build event after you have re-loaded the project.

Now as promised, the assembly version is available to your post build event with this macro:

@(VersionNumber)

Done!

As a workaround I've written a managed console application which takes the target as a parameter, and returns the version number.

I'm still interested to hear a simpler solution - but I'm posting this in case anyone else finds it useful.

using System;
using System.IO;
using System.Diagnostics;
using System.Reflection;

namespace Version
{
    class GetVersion
    {
        static void Main(string[] args)
        {
            if (args.Length == 0 || args.Length > 1) { ShowUsage(); return; }

            string target = args[0];

            string path = Path.IsPathRooted(target) 
                                ? target 
                                : Path.GetDirectoryName(Process.GetCurrentProcess().MainModule.FileName) + Path.DirectorySeparatorChar + target;

            Console.Write( Assembly.LoadFile(path).GetName().Version.ToString(2) );
        }

        static void ShowUsage()
        {
            Console.WriteLine("Usage: version.exe <target>");
        }
    }
}

If you prefer scripting these methods might also work for you:

If you are using the post-build event, you can use the filever.exe tool to grab it out of the already built assembly:

for /F "tokens=4" %%F in ('filever.exe /B /A /D bin\debug\myapp.exe') do (
  set VERSION=%%F
)
echo The version is %VERSION%

Get filever.exe from here: http://support.microsoft.com/kb/913111

If you are using the pre-build event, you can take it out of the AssemblyInfo.cs file as follows:

set ASMINFO=Properties\AssemblyInfo.cs
FINDSTR /C:"[assembly: AssemblyVersion(" %ASMINFO% | sed.exe "s/\[assembly: AssemblyVersion(\"/SET CURRENT_VERSION=/g;s/\")\]//g;s/\.\*//g" >SetCurrVer.cmd
CALL SetCurrVer.cmd
DEL SetCurrVer.cmd
echo Current version is %CURRENT_VERSION%

This uses the unix command line tool sed, which you can download from many places, such as here: http://unxutils.sourceforge.net/ - iirc that one works ok.