How to check the version of an assembly (dll)?

Question

I have c# application and when I made a change, I am getting the error message:

An unhandled exception of type 'System.TypeLoadException' occurred in WindowsFormsApplication1.exe

Additional information: Could not load type
'TradeIdeas.TIProData.OddsMakerColumnConfiguration' from assembly 'TIProData, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null’.

This message says the version number of dll (TIProData) is 1.0.0.0. I think there is a later version available. How can I tell the version number of a dll on my machine?

Citation

RIght click on the DLL go to Properties > Details. Version 1.0.0.0 Looks like its a development version of the DLL – Adaline

That is the file version, not the assembly version @AlexAnderson – Louvain

Open csproj file in text editor and find that dll reference, you can change version there, seems there is 1.0.0.0 hard coded – Casi

See powershell commands in #3267509 – Plankton

Does this answer your question? How can I get the assembly file version – Plankton

Answer 1

You can use JetBrains dotPeek (free), Reflector, ILDASM or ILSpy to get the assembly version.

You usually can find ILDASM in C:\Program Files (x86)\Microsoft SDKs\Windows\v8.1A\bin\NETFX 4.5.1 Tools\ildasm.exe (where v8.1A is the version of the Windows SDK installed).

ILDASM:

Reflector:

Louvain

Or Jetbrains dotPeek, which is also free. – Johannisberger

Btw it is absurd how hard Microsoft makes something this basic – Squeteague

Why is it different from the dll version from windows explorer file details? – Hammock

Answer 2

There is a couple of ways to do it:

• If you reference the dll in Visual Studio right click it (in ProjectName/References folder) and select "Properties" you have "Version" and "Runtime Version" there.

• In File Explorer when you right click the dll file and select properties there is a "File Version" and "Product Version" there.

• Alternatively, investigate it in code:

  Assembly assembly = Assembly.LoadFrom("TestAssembly.dll");
  Version ver = assembly.GetName().Version;
  

Gangrel

Caution - the "FileVersion" shown in the properties tab is NOT the same thing as AssemblyVersion which is the id used for binding redirects or assembly loading. – Karlakarlan

@Karlakarlan Yes! This has bitten me a few times. A workaround I found is to open the DLL with 7-zip and read the Assembly Version from .rsrc/version.txt . Baffles me why this isn't displayed in the File Properties dialog along with the rest of it. – Trichomoniasis

You should remove the middle bullet mentioning File Version and Product Version. It is true, but it implies that these are synonymous with the assembly version because that was the question and you have listed it as one of the "ways to do it". – Phuongphycology

Answer 3

You can use AssemblyName.GetAssemblyName(string path) from a little util app.

Further details here on MSDN.

Thornburg

Answer 4

If you know Class, that belongs to assembly, you can use GetTypeInfo

var runtimeVersion = typeof(MyClass)
.GetTypeInfo()
.Assembly
.GetCustomAttribute<AssemblyFileVersionAttribute>();

var version = runtimeVersion.Version;

 

The example is for .Net Core from https://developers.de/blogs/damir_dobric/archive/2017/06/27/how-to-deal-with-assembly-version-in-net-core.aspx

Plankton

Answer 5

From Powershell (PSCore): $assembly = [System.Reflection.Assembly]::LoadFrom("$pwd\System.Memory.dll") Besides $assembly.FullName you can pick up any other prop from the object.

Smukler

This approach silently gives the wrong answer if a DLL with the same name but in a different folder happens to be loaded already by the PowerShell process. In that case, it gives the assembly version of the already loaded DLL. – Caia

Answer 6

Inspired by JamesLucas' answer, you can create this assversion.fsx script and just run it with dotnet fsi asseversion.fsx ./path/to/your.dll:

if fsi.CommandLineArgs.Length < 2 then
    System.Console.Error.WriteLine("Please supply assembly path")
    exit 1
let arg = fsi.CommandLineArgs.[1]
System.Console.WriteLine(arg)
System.Console.WriteLine(System.Reflection.AssemblyName.GetAssemblyName(arg).ToString())

Danford