CA1000: Do not declare static members on generic types
TypeName |
DoNotDeclareStaticMembersOnGenericTypes |
CheckId |
CA1000 |
Category |
Microsoft.Design |
Breaking Change |
Breaking |
Cause
An externally visible generic type contains a static (Shared in Visual Basic) member.
Rule Description
When a static member of a generic type is called, the type argument must be specified for the type. When a generic instance member that does not support inference is called, the type argument must be specified for the member. The syntax for specifying the type argument in these two cases is different and easily confused, as the following calls demonstrate:
' Shared method in a generic type.
GenericType(Of Integer).SharedMethod()
' Generic instance method that does not support inference.
someObject.GenericMethod(Of Integer)()
// Static method in a generic type.
GenericType<int>.StaticMethod();
// Generic instance method that does not support inference.
someObject.GenericMethod<int>();
Generally, both of the prior declarations should be avoided so that the type argument does not have to be specified when the member is called. This results in a syntax for calling members in generics that is no different from the syntax for non-generics. For more information, see CA1004: Generic methods should provide type parameter.
How to Fix Violations
To fix a violation of this rule, remove the static member or change it to an instance member.
When to Suppress Warnings
Do not suppress a warning from this rule. Providing generics in a syntax that is easy to understand and use reduces the time that is required to learn and increases the adoption rate of new libraries.
Related Rules
CA1005: Avoid excessive parameters on generic types
CA1010: Collections should implement generic interface
CA1002: Do not expose generic lists
CA1006: Do not nest generic types in member signatures
CA1004: Generic methods should provide type parameter
CA1003: Use generic event handler instances
CA1007: Use generics where appropriate