Clarify CS0112 scope for C# 11 static interface members

[Copilot]

CS0112 docs currently imply static can’t combine with abstract/virtual in all contexts. Since C# 11 allows static abstract and static virtual on specific interface members, the guidance needed scope clarification.

• Scope correction

  • Updated the CS0112 lead sentence to explicitly limit the error to classes and structs.

• Rule clarification

  • Revised explanatory text to state that override/virtual/abstract + static is invalid in class/struct member declarations.

• C# 11 exception added

  • Added a direct note that interface methods, properties, events, and operators can use static abstract and static virtual.

• Consistency cleanup

  • Normalized keyword formatting in the rule sentence to use inline code style consistently.

A static member 'function' in a class or struct cannot be marked as override, virtual, or abstract.

Any method declaration in a class or struct that uses the `override`, `virtual`, or `abstract` keyword cannot also use the `static` keyword.

Starting in C# 11, interface methods, properties, events, and operators can use `static abstract` or `static virtual`.

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Internal previews

📄 File	🔗 Preview link
docs/csharp/misc/cs0112.md	docs/csharp/misc/cs0112

[BillWagner]

@copilot Address my comment on L17 and this is ready.

[Copilot]

@copilot Address my comment on L17 and this is ready.

Addressed in commit fd9d4209. The CS0112 page now states the pre-C# 11 restriction and explicitly describes the C# 11 exception for static abstract and static virtual interface members. No UI changes were made (documentation-only update).

[BillWagner]

This is ready for final review.

[Copilot]

Pull request overview

Clarifies the scope of compiler error CS0112 so the guidance doesn’t conflict with C# 11’s support for static abstract and static virtual interface members.

Changes:

• Updates the CS0112 lead sentence to scope the rule to class and struct members.
• Revises the explanatory text to consistently format keywords and clarify invalid modifier combinations.
• Adds a note calling out the C# 11 interface-member exception for static abstract/static virtual.