Code inspection: Property can be made init-only (non-private accessibility)

This inspection identifies properties that are only initialized in a constructor and suggests replacing their set accessor with the init accessor.

The init accessor in C# 9.0 and onwards allows properties to be made immutable in a more flexible way than before. Unlike with a readonly field or get-only property, an init-only property can be set only during object initialization. This helps maintain the immutability of objects after they are created, leading to safer and often simpler code.

            
public class Blog
{
    public Blog(string name)
    {
        Name = name;
    }
    public string Name { get; set; }
}

        

            
public class Blog
{
    public Blog(string name)
    {
        Name = name;
    }
    public string Name { get; init; }
}

        

For the solution-wide inspection to work, you need to enable at least one of the following:

Simplified global usage checking: select Show unused non-private type members when solution-wide analysis is off on the Editor | Inspection Settings page of JetBrains Rider settings Ctrl+Alt+S.
Solution-wide analysis: select Enable solution-wide analysis on the Editor | Inspection Settings page of JetBrains Rider settings Ctrl+Alt+S.

Note that even if the reported accessor has no direct usages in your solution, there could be cases where it is used indirectly — for example, via reflection — or it could just be designed as public API. In all those cases, you would want to suppress the usage-checking inspection for the accessor in one of the following ways:

The recommended way is to decorate the implicitly used accessor with a code annotation attribute. There are two attributes for this purpose: [UsedImplicitly] and [PublicAPI], which are functionally similar, but let you and your teammates understand how the accessor is actually used.
You can also suppress usage-checking inspections with any custom attribute. To do so, mark the definition of that attribute with the [MeansImplicitUse] attribute.
And finally, you can suppress a specific usage-checking inspection as any other code inspection with a suppression comment or a suppression attribute.

Last modified: 27 May 2024