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C#

C# static code analysis

Unique rules to find Bugs, Vulnerabilities, Security Hotspots, and Code Smells in your C# code

  • All rules 493
  • Vulnerability46
  • Bug88
  • Security Hotspot24
  • Code Smell335

  • Quick Fix 61
Filtered: 28 rules found
convention
    Impact
      Clean code attribute
        1. Literal suffixes should be upper case

           Code Smell
        2. Method overloads should be grouped together

           Code Smell
        3. Operator overloads should have named alternatives

           Code Smell
        4. Properties should be preferred

           Code Smell
        5. Type names should not match namespaces

           Code Smell
        6. Exceptions should provide standard constructors

           Code Smell
        7. Event Handlers should have the correct signature

           Code Smell
        8. Arguments of public methods should be validated against null

           Code Smell
        9. Parameter names should not duplicate the names of their methods

           Code Smell
        10. Attribute, EventArgs, and Exception type names should end with the type being extended

           Code Smell
        11. Non-flags enums should not be used in bitwise operations

           Code Smell
        12. Members should not be initialized to default values

           Code Smell
        13. Flags enumerations zero-value members should be named "None"

           Code Smell
        14. Enumeration type names should not have "Flags" or "Enum" suffixes

           Code Smell
        15. Enumeration types should comply with a naming convention

           Code Smell
        16. Classes named like "Exception" should extend "Exception" or a subclass

           Code Smell
        17. Underscores should be used to make large numbers readable

           Code Smell
        18. An abstract class should have both abstract and concrete methods

           Code Smell
        19. Multiple variables should not be declared on the same line

           Code Smell
        20. Track lack of copyright and license headers

           Code Smell
        21. Logger fields should be "private static readonly"

           Code Smell
        22. Statements should be on separate lines

           Code Smell
        23. Files should end with a newline

           Code Smell
        24. A close curly brace should be located at the beginning of a line

           Code Smell
        25. Tabulation characters should not be used

           Code Smell
        26. Lines should not be too long

           Code Smell
        27. Types should be named in PascalCase

           Code Smell
        28. Methods and properties should be named in PascalCase

           Code Smell

        An abstract class should have both abstract and concrete methods

        consistency - conventional
        maintainability
        Code Smell
        • convention

        A class with only abstract methods and no inheritable behavior should be converted to an interface.

        Why is this an issue?

        How can I fix it?

        More Info

        The purpose of an abstract class is to provide some overridable behaviors while also defining methods that are required to be implemented by sub-classes.

        A class that contains only abstract methods, often called pure abstract class, is effectively an interface, but with the disadvantage of not being able to be implemented by multiple classes.

        Using interfaces over pure abstract classes presents multiple advantages:

        • Multiple Inheritance: Unlike classes, an interface doesn’t count towards the single inheritance limit in C#. This means a class can implement multiple interfaces, which can be useful when you need to define behavior that can be shared across multiple classes.
        • Loose Coupling: Interfaces provide a way to achieve loose coupling between classes. This is because an interface only specifies what methods a class must have, but not how they are implemented. This makes it easier to swap out implementations without changing the code that uses them.
        • Polymorphism: Interfaces allow you to use polymorphism, which means you can use an interface type to refer to any object that implements that interface. This can be useful when you want to write code that can work with any class that implements a certain interface, without knowing what the actual class is.
        • Design by contract: Interfaces provide a clear contract of what a class should do, without specifying how it should do it. This makes it easier to understand the intended behavior of a class, and to ensure that different implementations of an interface are consistent with each other.

        Exceptions

        abstract classes that contain non-abstract methods, in addition to abstract ones, cannot easily be converted to interfaces, and are not the subject of this rule:

        public abstract class Lamp // Compliant: Glow is abstract, but FlipSwitch is not
        {
          private bool switchLamp = false;
        
          public abstract void Glow();
        
          public void FlipSwitch()
          {
            switchLamp = !switchLamp;
            if (switchLamp)
            {
              Glow();
            }
          }
        }
        

        Notice that, since C# 8.0, you can also define default implementations for interface methods, which is yet another reason to prefer interfaces over abstract classes when you don’t need to provide any inheritable behavior.

        However, interfaces cannot have fields (such as switchLamp in the example above), and that remains true even in C# 8.0 and upwards. This can be a valid reason to still prefer an abstract class over an interface.

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