Conditional Attribute

Conditional attribute is under System.Diagnostics name space.

When keyword like "DEBUG" defined (default situation), the function performed.

When keyworkd "Debug" undef, the function just skipped.

 ref:

https://msdn.microsoft.com/en-us/library/system.diagnostics.conditionalattribute(v=vs.110).aspx

http://www.runoob.com/csharp/csharp-attribute.html