Form View Designer is NOT working in Visual Studio 2019 with using c# .NET Core 3.1

Question

When I am opening a visual studio project with VB.NET then Form view designer is automatically open but I open a new project with C# .NET Core 3.1 with Windows form then it is showing code of form1.cs. I tried alternate from solution explorer as well from view>>designer option but still not showing a form. What is going wrong there? I made google search for this but not found useful on this.

Please check in the image that I'm getting during the opening project.:

Solution 1

Make sure you only have the form declared in your file. If you have more than one class defined, the design viewer will not work.

Solution 2

Preview VS2019 until v16.4 needs a VSIX separate installation extension. Now you can update your Preview of VS2019 (to 16.5 or higher) and you don't need this extension. You can do it through the menu "Help" of VS IDE.

After update go to ... Tools > Options > Environment > Preview Features and check "Use previews of the .NET Core SDK (requires restart)" option.

Restart VS and it will work ;)

-Edit April 2020

You can install the Preview Version that will have all these and more feature enabled. As its a preview it may be unstable but it can run side by side with your normal version in case something is broken in preview

visualstudio.microsoft.com/vs/preview