I want to allow internal required members in public class if have only internal constructors.

[ChanyaKushima]

Proposal Details

1. Condition: If a public class does not expose any public constructors (i.e., all constructors are less accessible than public), then it should be permissible to declare its required properties at the same or narrower accessibility level as those constructors.
2. Objective: This allows developers to create a public class (for metadata, reflection, or other advanced scenarios) that cannot be instantiated outside the intended scope. Since no external code can instantiate the class, the required members can remain at a restricted visibility (e.g., internal, protected internal, or even private), thereby controlling exactly who can access or initialize those members.

Example

public class MyClass
{
    internal required string MyRequiredProp { get; init; }

    internal MyClass() 
    {
        // Optionally set default values
    }

    internal MyClass(string value)
    {
        MyRequiredProp = value;
    }
}

• The class is public, but its constructors are all internal.
• The required property MyRequiredProp is also internal.
• No external assembly can instantiate MyClass, so external code does not need to see or set MyRequiredProp.

Currently, attempting to declare required members at a lower accessibility level than the class itself—while the class is public but has non-public constructors—leads to compiler error CS9032 in C#. This error indicates that the accessibility rules for required members are tied to the class's declared visibility rather than the actual accessibility of its constructors.

[iam3yal]

@ChanyaKushima #6435, #7618