csharper_attributes

gistfile1.md

#C# Attributes

WIP

Attributes are just meta-data associated to the code.

You can create your own:

• Create a child class of System.Attribute
• The name of your attribute class should end with Attribute (convention sufix)
  • Omit the subfix when actually using the attribute.
• (optional) Use the AttributeUsage attribute to specify to which constructions the attribute may apply to (Class, Interface, Methods, Constructors...)

Example:

[AttributeUsageAttribute(AttributeTargets.All, Inherited = true, AllowMultiple = false)]
public MyOwnAttribute : System.Attribute
{
}

...

[MyOwn]
public class MyClass
{

   [MyOnw]
   public MyClass() 
   {
   }
}

AttributeTargets reference

Some useful attributes

####ObsoleteAttribute

Marks a class / method / interface as obsolete. The compiler will throw a warning each time we reference the construct.

[Obsolete]
int DeprecatedMethod()
{
}

Although it is optional, it is highly recommended that you leave a meaningful warning message:

[Obsolete("To be deprecated in v1.1. Use NewMethod instead")]
int DeprecatedMethod()
{
}

####ConditionalAttribute

Compiles a method (or class) iff a preprocessor variable is set.

// The conditional method MUST NOT return any value (void)
[Conditional("DEBUG")]
void ConditionalMethod()
{
}

The above code is equivalent to:

#if DEBUG
void ConditionalMethod()
{
}
#endif