CA1711: Identifiers should not have incorrect suffix


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TypeName IdentifiersShouldNotHaveIncorrectSuffix
CheckId CA1711
Category Microsoft.Naming
Breaking Change Breaking


An identifier has an incorrect suffix.

Rule Description

By convention, only the names of types that extend certain base types or that implement certain interfaces, or types derived from these types, should end with specific reserved suffixes. Other type names should not use these reserved suffixes.

The following table lists the reserved suffixes and the base types and interfaces with which they are associated.

Suffix Base type/Interface
Attribute System.Attribute
Collection System.Collections.ICollection






Dictionary System.Collections.IDictionary

EventArgs System.EventArgs
EventHandler An event-handler delegate
Exception System.Exception
Permission System.Security.IPermission
Queue System.Collections.Queue
Stack System.Collections.Stack
Stream System.IO.Stream

In addition, the following suffixes should not be used:

  • Delegate

  • Enum

  • Impl - use 'Core' instead

  • Ex or similar suffix to distinguish it from an earlier version of the same type

    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.

How to Fix Violations

Remove the suffix from the type name.

When to Suppress Warnings

Do not suppress a warning from this rule unless the suffix has an unambiguous meaning in the application domain.

CA1710: Identifiers should have correct suffix

See Also

Attributes NIB: Events and Delegates