Assembly: mscorlib (in mscorlib.dll)
[SerializableAttribute] [AttributeUsageAttribute(AttributeTargets::Class|AttributeTargets::Method, AllowMultiple=true)] [ComVisibleAttribute(true)] public ref class ConditionalAttribute sealed : public Attribute
/** @attribute SerializableAttribute() */ /** @attribute AttributeUsageAttribute(AttributeTargets.Class|AttributeTargets.Method, AllowMultiple=true) */ /** @attribute ComVisibleAttribute(true) */ public final class ConditionalAttribute extends Attribute
Methods decorated with the ConditionalAttribute attribute are always compiled into Microsoft intermediate language (MSIL), but calls to the methods can not be made at run time. If the method has arguments, they are type-checked at run time, but not evaluated.
Visual Studio 2005 compiles Release builds with the TRACE conditional compilation constant defined, and Debug builds with both the DEBUG and TRACE constants defined, by default. For command-line builds, you must specify all conditional compilation constants.
A ConditionalAttribute that has an associated ConditionString can be attached to the definition of a method, creating a conditional method. Thereafter, when a compiler encounters a call to that method, it can choose to ignore the call unless a compilation variable is defined at the site of the call, with a value that matches in a case-sensitive manner the ConditionString supplied to the ConditionalAttribute.
Compilers might provide several techniques to define such compilation variables, such as:
Compiler command-line switches (for example, /define:DEBUG).
Environment variables in the operating system shell (for example, SET DEBUG=1).
Pragmas in the source code (for example, #define DEBUG, to define the compilation variable, or #undef DEBUG to undefine it).
CLS-compliant compilers are permitted to ignore the ConditionalAttribute.
For more information about using attributes, see Extending Metadata Using Attributes.
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.