Upgrading WinForms App To Support .NET Core 3.0

Jefferson S. Motta

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Jefferson S. Motta7y ago
Krishna, just remove the file resources.resx; reopen the project; go to project properties; create a new resource; select images; and drag images directly from the "Resources" folder. Note that if you have other resources desides images, they will need to be recreated.
krishna Prasad7y ago
Can you share the docs you used to so?? I made changes described in https://docs.microsoft.com/en-us/dotnet/core/porting/index and explained in video https://devblogs.microsoft.com/dotnet/how-to-port-desktop-applications-to-net-core-3-0/. For me everything worked until i build the solution and then I ended up getting few run-time errors like "Exception thrown: 'System.IO.FileNotFoundException' in some.exe"
- Jefferson S. Motta7y ago
  I try my self. Try remove <PublishTrimmed>true</PublishTrimmed> or change to <PublishTrimmed>false</PublishTrimmed> . Let me know. Send me in private message the exception too.
- Jefferson S. Motta7y ago
  May this help too: https://www.telerik.com/blogs/how-to-port-desktop-applications-to-net-core-3-0
- krishna Prasad7y ago
  Thank you. Can i get more light on how you handled the resource file and .setting file references? i.e referencing image resource. In winform i use this ~ "global::Application.Properties.Resources.test_image"
Jefferson S. Motta7y ago
Pritesh, look this POST,https://devblogs.microsoft.com/dotnet/announcing-net-core-3-0/.... Note: Windows Forms and WPF apps only work on Windows.
Pritesh Maturkar7y ago
Thanks. I have a question. can we dotnet core desktop run on cross platform ?
- Jefferson S. Motta7y ago
  Yes. But not WinForms subsystem nor any Win32 API.
- Pritesh Maturkar7y ago
  Thanks. but I am not getting. suppose. I have create desktop applications using .net core so can use applications in cross platform?
Ehsan Sajjad7y ago
Thanks for sharing your experience, it will be helpful for many surely.

.NET Core 3.0

.NET Core 3.0 is a new incarnation for .NET Framework with upgrades, launched on 9/23/2019. .NET Core 3.0 has compatibility with several distros of Linux and runs on macOS too. .NET Core 3.0 has support for WinForms, but you will not be able to run it on Linux and macOS. The output of the conversion will be a single EXE file.

Upgrading

I upgraded a big WinForms App to .NET Core 3.0. It took me one day, but not because it was hard but because the online resources available are confusing.

The first step was to create a new Solution, and one by one project from the original solution, I did from a scratch.

After that, I copied all project files and the folders Resources and Properties, on the folder Properties just delete AssemblyInfo.cs file and *.licx if there are some.

While upgrading probably you will get some assemblies that are missing or not compatible.

Look on NuGet and search for the namespace, if it is from Microsoft, or try a search for a replacement in .NET Core 3.0. In my case two assemblies were not crucial so I disabled code with:

#if (DLL1)
// ~code
#endif

Configuring the project to Run with a Single EXE

This sample is for Windows, deployed for win-x86, that runs both on 32bits and 64bits Windows OS.

While configuring to publish, I found a bug in this process. The fix: to add a singular key: RuntimeIdentifier because an error occurred NETSDK1097, that I followed to https://github.com/dotnet/core/issues/2851 with no solution.

So I interpreted literally the message and presumed that it was a mistake from the designer.

To make it work, add these keys to .csproj,

<PropertyGroup>
<OutputType>WinExe</OutputType>
<TargetFramework>netcoreapp3.0</TargetFramework>
<UseWindowsForms>true</UseWindowsForms>
<PublishSingleFile>true</PublishSingleFile>
<PublishTrimmed>true</PublishTrimmed>
<TieredCompilationQuickJit>true</TieredCompilationQuickJit>
<PublishReadyToRun>true</PublishReadyToRun>
<RuntimeIdentifier>win-x86</RuntimeIdentifier>
<RuntimeIdentifiers>win-x86</RuntimeIdentifiers>
</PropertyGroup>

Note that the this singular key is needed to avoid the error, although duplicated in plural:

<RuntimeIdentifier>win-x86</RuntimeIdentifier>

Publish error

*It is not supported to publish an application to a single-file without specifying a RuntimeIndentifier. Please either specify a RuntimeIdentifier or set PublishSingleFile to false.

Internal message error on .tmp file:

System.AggregateException: One or more errors occurred. ---> System.Exception: Publishing failed.
--- End of inner exception stack trace ---
at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
at Microsoft.Publish.Framework.Model.DefaultPublishSteps.<>c__DisplayClass26_0.<IsBuildCompletedSuccessfully>b__2()
at System.Threading.Tasks.Task`1.InnerInvoke()
at System.Threading.Tasks.Task.Execute()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.Publish.Framework.Model.DefaultPublishSteps.<DefaultCorePublishStep>d__23.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.Publish.Framework.ViewModel.ProfileSelectorViewModel.<RunPublishTaskAsync>d__202.MoveNext()
---> (Inner Exception #0) System.Exception: Publishing failed.<---
System.Exception: Publishing failed.
===================

Publising

Now you need to create a profile for this,

If your application will run only in process x64, you can select another runtime target.

Conclusion

My app started very fast as a single exe file. But the size was about 300MB and takes more time to build and generate this file.

I hope this post helps you deliver a better and faster solution for your end-user.

UPDATE 10/05/2019:

If you are using:

SqlConnection.GetSchema Method

you will get run time error: "Column requires a valid datatype."

To fix it set PublishTrimmed to false: <PublishTrimmed>false</PublishTrimmed>

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.
************** Exception Text **************
System.ArgumentException: Column requires a valid DataType.
at System.Data.DataColumn.set_DataType(Type value)
at System.Data.XSDSchema.SetProperties(Object instance, XmlAttribute[] attrs)
at System.Data.XSDSchema.HandleElementColumn(XmlSchemaElement elem, DataTable table, Boolean isBase)
at System.Data.XSDSchema.HandleParticle(XmlSchemaParticle pt, DataTable table, ArrayList tableChildren, Boolean isBase)
at System.Data.XSDSchema.HandleComplexType(XmlSchemaComplexType ct, DataTable table, ArrayList tableChildren, Boolean isNillable)
at System.Data.XSDSchema.InstantiateTable(XmlSchemaElement node, XmlSchemaComplexType typeNode, Boolean isRef)
at System.Data.XSDSchema.HandleTable(XmlSchemaElement node)
at System.Data.XSDSchema.HandleDataSet(XmlSchemaElement node, Boolean isNewDataSet)
at System.Data.XSDSchema.LoadSchema(XmlSchemaSet schemaSet, DataSet ds)
at System.Data.DataSet.ReadXSDSchema(XmlReader reader, Boolean denyResolving)
at System.Data.DataSet.ReadXml(XmlReader reader, Boolean denyResolving)
at System.Data.DataSet.ReadXml(Stream stream)
at System.Data.ProviderBase.DbMetaDataFactory.LoadDataSetFromXml(Stream XmlStream)
at System.Data.ProviderBase.DbMetaDataFactory..ctor(Stream xmlStream, String serverVersion, String normalizedServerVersion)
at System.Data.SqlClient.SqlConnectionFactory.CreateMetaDataFactory(DbConnectionInternal internalConnection, Boolean& cacheMetaDataFactory)
at System.Data.ProviderBase.DbConnectionFactory.GetMetaDataFactory(DbConnectionPoolGroup connectionPoolGroup, DbConnectionInternal internalConnection)
at System.Data.ProviderBase.DbConnectionInternal.GetSchema(DbConnectionFactory factory, DbConnectionPoolGroup poolGroup, DbConnection outerConnection, String collectionName, String[] restrictions)
at System.Data.SqlClient.SqlConnection.GetSchema(String collectionName, String[] restrictionValues)
at System.Data.SqlClient.SqlConnection.GetSchema(String collectionName)