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I recently updated from a relatively recent version of VS Community 2022 to 17.2.2, and, in a WinUI 3 C# app, started getting an error message in the generated file Settings11.Designer.cs, "The type name 'ApplicationSettingsBase' could not be found in the namespace 'System.Configuration'." I went through the release notes for recent VS releases, but didn't see anything pertaining to configuration settings. Have there been changes to configuration settings? Any suggestions for how to proceed?
Thanks,
Daniel
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Hi Daniel, welcome to Microsoft Q&A forum. Could you share me the steps to reproduce this issue? BTW, are you using .NET Framework, or .NET/.NET Core? It seems to be a .NET Core related component missing or using the wrong .NET framework.
You are better off setting up an appsettings.json file for storing information rather than old school app.config. Using a json file can be read and edited easily.
Simple example for storing database connections for three environments, application title. Read/write is done via serializing and deserializing using System.Text.Json via a class/model which represents information in the json file.
{
"ConnectionsConfiguration": {
"ActiveEnvironment": "Development",
"Development": "Dev connection string goes here",
"Stage": "Stage connection string goes here",
"Production": "Prod connection string goes here"
},
"Settings": {
"Title": "Code sample"
}
}
Thanks for the suggestion, I'll look into that.
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I have a problem with a VB.NET class library I upgraded from .NET 4.8 to .NET Core 8. After that, the error is in the "Settings.Designer.vb" file. That is auto-generated, and contains the following code extract containing the error:
Can you please advise how to fix? I am not finding any ready answer on the web yet.
Option Strict On
Option Explicit On
Namespace My
<Global.System.Runtime.CompilerServices.CompilerGeneratedAttribute(), _
Global.System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "17.3.0.0"), _
Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)> _
Partial Friend NotInheritable Class MySettings
Inherits Global.System.Configuration.ApplicationSettingsBase
Private Shared defaultInstance As MySettings = CType(Global.System.Configuration.ApplicationSettingsBase.Synchronized(New MySettings()),MySettings)
...
Thanks for replying, I'm using .NET Core, 6. And you're right, it's a missing assembly, re-reading the error message, it actually says that the class ApplicationSettingsBase has been moved to System.Configuration.ConfigurationManager. I'm assuming that happened recently since I last upgraded, I guess I should have read the message more carefully before posting here! After installing System.Configuration.ConfigurationManager, it builds. This issue can be closed.