Flags enums should have plural names
Flags enums should have plural names
Microsoft docsDescription
Types that are marked with System.FlagsAttribute have names that are plural because the attribute indicates that more than one value can be specified. For example, an enumeration that defines the days of the week might be intended for use in an application where you can specify multiple days. This enumeration should have the System.FlagsAttribute and could be called 'Days'. A similar enumeration that allows only a single day to be specified would not have the attribute, and could be called 'Day'.
Naming conventions provide a common look for libraries that target the common language runtime. This reduces the learning curve that is required for new software libraries, and increases customer confidence that the library was developed by someone who has expertise in developing managed code.
Cause
An enumeration has the System.FlagsAttribute and its name does not end in 's'.
By default, this rule only looks at externally visible enumerations, but this is configurable.
How to fix violations
Make the name of the enumeration a plural word, or remove the System.FlagsAttribute attribute if multiple enumeration values should not be specified simultaneously.
Example
#pragma warning disable CA1714
// The code that's violating the rule is on this line.
#pragma warning restore CA1714When to suppress
It is safe to suppress a violation if the name is a plural word but does not end in 's'. For example, if the multiple-day enumeration that was described previously were named 'DaysOfTheWeek', this would violate the logic of the rule but not its intent. Such violations should be suppressed.