Add managed C#/VB declarations (DllImport + StructLayout) to PInvokeLib.dll reference article

[Copilot]

• Create C# snippet file with managed struct declarations (StructLayout) and DllImport prototypes matching pinvokelib.h
• Create VB snippet file with equivalent declarations
• Update marshalling-data-with-platform-invoke.md to include the C# and VB managed code sections
• Update article frontmatter with dev_langs and ai-usage
• Verify snippets compile correctly
• Fix library name consistency: change "Pinvoke.dll" to "PInvokeLib.dll" on line 58

Original prompt

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This section details on the original issue you should resolve

<issue_title>You're missing 50% of the example here</issue_title>
<issue_description>This is a great example EXCEPT that it doesn't show the DllImport or StructLayout details from C#, which is the other (necessary) 50% that makes this useful...

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Document Details

⚠ Do not edit this section. It is required for docs.microsoft.com ➟ GitHub issue linking.

• ID: 678eaef3-eec4-dc52-1234-37e220f84682
• Version Independent ID: 38b09163-65d8-4d6c-1394-401e080ed6f0
• Content: Marshaling Data with Platform Invoke
• Content Source: docs/framework/interop/marshaling-data-with-platform-invoke.md
• Product: dotnet-framework
• GitHub Login: @gewarren
• Microsoft Alias: dotnetcontent</issue_description>

Comments on the Issue (you are @copilot in this section)

@dotnet-bot This issue has been closed as part of the issue backlog grooming process outlined in #22351.

That automated process may have closed some issues that should be addressed. If you think this is one of them, reopen it with a comment explaining why. Tag the @dotnet/docs team for visibility.</comment_new>
<comment_new>@BillWagner
Thanks @mr-intj

reopening.</comment_new>

• Fixes You're missing 50% of the example here #18458

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Internal previews

📄 File	🔗 Preview link
docs/framework/interop/marshalling-data-with-platform-invoke.md	Marshalling Data with Platform Invoke

[BillWagner]

This looks good, and it's ready for final review.

[Copilot]

Pull request overview

This PR completes the PinvokeLib.dll example in marshalling-data-with-platform-invoke.md by adding the managed C# and Visual Basic declarations (struct mappings and DllImport signatures) that match the unmanaged header, and wiring those declarations into the article via snippet includes.

Changes:

• Added new C# and VB snippet projects containing managed StructLayout declarations and DllImport prototypes for PinvokeLib.dll.
• Updated the article to include “Managed type declarations” and “Managed function prototypes” sections that reference the new snippet files.
• Updated article metadata (ms.date, dev_langs, and ai-usage).

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
docs/framework/interop/marshalling-data-with-platform-invoke.md	Adds new managed-declarations subsections and snippet includes; updates frontmatter metadata.
docs/framework/interop/snippets/marshalling-data-with-platform-invoke/csharp/PInvokeLibManaged/NativeMethods.cs	Introduces the C# StructLayout types and DllImport signatures for PinvokeLib.dll.
docs/framework/interop/snippets/marshalling-data-with-platform-invoke/csharp/PInvokeLibManaged/PInvokeLibManaged.csproj	Adds a minimal C# project to host/compile the snippet source.
docs/framework/interop/snippets/marshalling-data-with-platform-invoke/csharp/PInvokeLibManaged/Program.cs	Adds a minimal entry point for the snippet project.
docs/framework/interop/snippets/marshalling-data-with-platform-invoke/vb/PInvokeLibManaged/NativeMethods.vb	Introduces the VB StructLayout types and DllImport signatures for PinvokeLib.dll.
docs/framework/interop/snippets/marshalling-data-with-platform-invoke/vb/PInvokeLibManaged/PInvokeLibManaged.vbproj	Adds a minimal VB project to host/compile the snippet source.
docs/framework/interop/snippets/marshalling-data-with-platform-invoke/vb/PInvokeLibManaged/Program.vb	Adds a minimal entry point for the VB snippet project.

[Copilot]

The section header is "PinvokeLib.dll", but the sentence immediately above this new paragraph still says the functions are provided by "Pinvoke.dll". Update that reference to "PinvokeLib.dll" so the library name is consistent throughout the section.

[BillWagner]

@copilot change the text on line 58 to use "PInvokeLib.dll"

[Copilot]

Fixed in commit 2b6c51a — "Pinvoke.dll" is now "PInvokeLib.dll".