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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: 11 rules found
finding
    Impact
      Clean code attribute
        1. Empty "default" clauses should be removed

           Code Smell
        2. Empty "case" clauses that fall through to the "default" should be omitted

           Code Smell
        3. Redundant property names should be omitted in anonymous classes

           Code Smell
        4. Declarations and initializations should be as concise as possible

           Code Smell
        5. Default parameter values should not be passed as arguments

           Code Smell
        6. Constructor and destructor declarations should not be redundant

           Code Smell
        7. Redundant parentheses should not be used

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

           Code Smell
        9. "catch" clauses should do more than rethrow

           Code Smell
        10. Redundant modifiers should not be used

           Code Smell
        11. "ToString()" calls should not be redundant

           Code Smell

        "ToString()" calls should not be redundant

        intentionality - clear
        maintainability
        Code Smell
        Quick FixIDE quick fixes available with SonarLint
        • finding
        • clumsy

        Why is this an issue?

        Invoking a method designed to return a string representation of an object which is already a string is a waste of keystrokes. Similarly, explicitly invoking ToString() when the compiler would do it implicitly is also needless code-bloat.

        This rule raises an issue when ToString() is invoked:

        • on a string
        • on a non-string operand to concatenation
        • on an argument to string.Format

        Noncompliant code example

        var s = "foo";
        var t = "fee fie foe " + s.ToString();  // Noncompliant
        var someObject = new object();
        var u = "" + someObject.ToString(); // Noncompliant
        var v = string.Format("{0}", someObject.ToString()); // Noncompliant
        

        Compliant solution

        var s = "foo";
        var t = "fee fie foe " + s;
        var someObject = new object();
        var u = "" + someObject;
        var v = string.Format("{0}", someObject);
        

        Exceptions

        The rule does not report on value types, where leaving off the ToString() call would result in automatic boxing.

        var v = string.Format("{0}", 1.ToString());
        
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          Available Since
          9.1
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          Developer Edition
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