C# Antipatterns
anti-patterns, c#
Solution
Rethrowing the exception incorrectly. To rethrow an exception :
try
{
// do some stuff here
}
catch (Exception ex)
{
throw ex; // INCORRECT
throw; // CORRECT
throw new Exception("There was an error"); // INCORRECT
throw new Exception("There was an error", ex); // CORRECT
}
Problem
To cut a long story short: I find the Java antipatterns an indispensable resource. For beginners as much as for professionals. I have yet to find something like this for C#. So I'll open up this question as community wiki and invite everyone to share their knowledge on this. As I am new to C#, I am strongly interested in this, but cannot start with some antipatterns :/ Here are the answers which I find specifically true for C# and not other languages. I just copy/pasted these! Consider throwing a look on the comments on these as well. Throwing `NullReferenceException` Throwing the wrong exception: ``` if (FooLicenceKeyHolder == null) throw new NullReferenceException(); ``` Properties vs. public Variables Public variables in classes (use a property instead). Unless the class is a simple Data Transfer Object. Not understanding that bool is a real type, not just a convention ``` if (myBooleanVariable == true) { ... } ``` or, even better ``` if (myBooleanVariable != false) { ... } ``` Constructs like these are often used by `C` and `C++` developers where the idea of a boolean value was just a convention (0 == false, anything else is true); this is not necessary (or desirable) in C# or other languages that have real booleans. Using `using()` Not making use of `using` where appropriate: ``` object variable; variable.close(); //Old code, use IDisposable if available. variable.Dispose(); //Same as close. Avoid if possible use the using() { } pattern. variable = null; //1. in release optimised away. 2. C# is GC so this doesn't do what was intended anyway. ```