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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: 12 rules found
design
    Impact
      Clean code attribute
        1. Interfaces for durable entities should satisfy the restrictions

           Code Smell
        2. Client instances should not be recreated on each Azure Function invocation

           Code Smell
        3. Multidimensional arrays should not be used

           Code Smell
        4. Strings or integral types should be used for indexers

           Code Smell
        5. Classes should not have only "private" constructors

           Bug
        6. Interfaces should not simply inherit from base interfaces with colliding members

           Code Smell
        7. Methods should not return values that are never used

           Code Smell
        8. Inner class members should not shadow outer class "static" or type members

           Code Smell
        9. "interface" instances should not be cast to concrete types

           Code Smell
        10. Two branches in a conditional structure should not have exactly the same implementation

           Code Smell
        11. String literals should not be duplicated

           Code Smell
        12. Utility classes should not have public constructors

           Code Smell

        "interface" instances should not be cast to concrete types

        adaptability - focused
        maintainability
        Code Smell
        • design

        Why is this an issue?

        Needing to cast from an interface to a concrete type indicates that something is wrong with the abstractions in use, likely that something is missing from the interface. Instead of casting to a discrete type, the missing functionality should be added to the interface. Otherwise there is a risk of runtime exceptions.

        Noncompliant code example

        public interface IMyInterface
        {
          void DoStuff();
        }
        
        public class MyClass1 : IMyInterface
        {
          public int Data { get { return new Random().Next(); } }
        
          public void DoStuff()
          {
            // TODO...
          }
        }
        
        public static class DowncastExampleProgram
        {
          static void EntryPoint(IMyInterface interfaceRef)
          {
            MyClass1 class1 = (MyClass1)interfaceRef;  // Noncompliant
            int privateData = class1.Data;
        
            class1 = interfaceRef as MyClass1;  // Noncompliant
            if (class1 != null)
            {
              // ...
            }
          }
        }
        

        Exceptions

        Casting to object doesn’t raise an issue, because it can never fail.

        static void EntryPoint(IMyInterface interfaceRef)
        {
          var o = (object)interfaceRef;
          ...
        }
        
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