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I am trying to create a custom build task that will be invoked by overriding the "AfterResGen" target. The build task receives the list of files (FileWrites) and needs to go through all the build generated ".resources" files, deserialize them, manipulate them a bit and finally update them.
According to the Task documentation, the assembly containing the custom Task must be a netstandard2.0 project, so I've been trying that. However, reading and deserializing the ".resources" files (at that point on the obj folder since this is mid build) using either the ResourceReader type or the DeserializingResourceReader type, throw exception on every .resource file with "Stream is not a valid resource file". Debugging this down to the ResourceReader's exception, seems that some "MagicNumber" doesn't match. For the record, I do have System.Resources.Extensions v8.0.0 Nuget referenced on that netstandard2.0 project.
I have also attempted to create the build task in a net8 assembly but that fails loading of the assembly during the build, complaining that System.Runtime v8.0.0 can't be found. Interestingly, the net8 build task is loaded successfully during build using "dotnet build" outside of VS, so I guess this problem has to do with the inability of VS to load build tasks from net8 assemblies. I tried using TaskFactory="TaskHostFactory" on the UsingTask element in the .targets file, but then it just complains about inability to load some other assemblies so that doesn't work either. At the moment, I'm stuck!
So, any thoughts on either a) How can I make the netstandard2.0 build task read the .resources files, deserialize and update during build or b) How can I make the net8 build task load and run when build is initiated from within Visual Studio ?
Palli
Not sure why I don't see the answer here that I was notified on via email, but I do realize that MSBuild is what's running the tasks and that I'm restricted to netstandard2.0 for the task. That fact alone doesn't really help because using a netstandard2.0 (or .net4.8) assembly for the task, the ResourceReader (and DeserializingResourceReader) can't read that .resources file so I can't access them.
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Please read my entire answer. You need to provide us the code otherwise we can only assume your code is wrong.
Hi Michael. Sorry about that. Your answer just didn't show despite of multiple refreshes. In trying to prepare a trivial sample, I figured out that if you only have primitive type resources in the .resx files, you can use ResourceReader type to read them. If you add images or other files to the resx file, you will have to use DeserializingResourceReader type to read them. With that, and the fact you have already confirmed, that I will have to downgrade my build task assembly from net8 to netstandard2.0 (or .net 4.8), I suspect that the bad stream exception may be what's been misleading me while having the build task in netstandard2.0/.net 4.8. The thing is that the types being deserialized are found in a net8 assembly, so that will never work. I'll need to do some refactoring on those types to further test this. The DeserializingResourceReader can indeed deserialize that .resource file provided it only has known .net types, like image or string, but not when deserializing types that are in my net8 assembly. This gets me one step closer so thanks for your help.
Glad to hear you got it figured out. Yes I have the same issue with answers and comments sometimes not appearing even after the notification. This has been a known bug in the forums since the migration. Seems like their caching doesn't work correctly in a lot of cases.
VS doesn't build your app, MSBuild does. MSBuild is what hosts the build tasks and it is a NET 4.x app so you are limited to netstandard2.0 for compiled build tasks. dotnet is compiled against whatever the latest framework version is that you're targeting so you could use any compiled build task but of course only with dotnet.
Can you please post the code you're using to try to read the resource file?
Have you tried using your code in a standalone app and reading a binary resource file directly? This would help ensure your code is working against a valid resources file before introducing the complexity of build outputs.