System Namespace

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Contains fundamental classes and base classes that define commonly used value and reference data types, events and event handlers, interfaces, attributes, and processing exceptions.

Classes

Name	Description
AccessViolationException	The exception that is thrown when there is an attempt to read or write protected memory.
ActivationContext	Identifies the activation context for the current application. This class cannot be inherited.
Activator	Contains methods to create types of objects locally or remotely, or obtain references to existing remote objects. This class cannot be inherited.
AggregateException	Represents one or more errors that occur during application execution.
AppContext	Provides members for setting and retrieving data about an application's context.
AppDomain	Represents an application domain, which is an isolated environment where applications execute. This class cannot be inherited.
AppDomainManager	Provides a managed equivalent of an unmanaged host.
AppDomainSetup	Represents assembly binding information that can be added to an instance of AppDomain.
AppDomainUnloadedException	The exception that is thrown when an attempt is made to access an unloaded application domain.
ApplicationException	Serves as the base class for application-defined exceptions.
ApplicationId	Contains information used to uniquely identify a manifest-based application. This class cannot be inherited.
ApplicationIdentity	Provides the ability to uniquely identify a manifest-activated application. This class cannot be inherited.
ArgumentException	The exception that is thrown when one of the arguments provided to a method is not valid.
ArgumentNullException	The exception that is thrown when a null reference (`Nothing` in Visual Basic) is passed to a method that does not accept it as a valid argument.
ArgumentOutOfRangeException	The exception that is thrown when the value of an argument is outside the allowable range of values as defined by the invoked method.
ArithmeticException	The exception that is thrown for errors in an arithmetic, casting, or conversion operation.
Array	Provides methods for creating, manipulating, searching, and sorting arrays, thereby serving as the base class for all arrays in the common language runtime.
ArrayTypeMismatchException	The exception that is thrown when an attempt is made to store an element of the wrong type within an array.
AssemblyLoadEventArgs	Provides data for the AssemblyLoad event.
Attribute	Represents the base class for custom attributes.
AttributeUsageAttribute	Specifies the usage of another attribute class. This class cannot be inherited.
BadImageFormatException	The exception that is thrown when the file image of a dynamic link library (DLL) or an executable program is invalid.
BinaryData	A lightweight abstraction for a payload of bytes that supports converting between string, stream, JSON, and bytes.
BitConverter	Converts base data types to an array of bytes, and an array of bytes to base data types.
Buffer	Manipulates arrays of primitive types.
CannotUnloadAppDomainException	The exception that is thrown when an attempt to unload an application domain fails.
CharEnumerator	Supports iterating over a String object and reading its individual characters. This class cannot be inherited.
CLSCompliantAttribute	Indicates whether a program element is compliant with the Common Language Specification (CLS). This class cannot be inherited.
Console	Represents the standard input, output, and error streams for console applications. This class cannot be inherited.
ConsoleCancelEventArgs	Provides data for the CancelKeyPress event. This class cannot be inherited.
ContextBoundObject	Defines the base class for all context-bound classes.
ContextMarshalException	The exception that is thrown when an attempt to marshal an object across a context boundary fails.
ContextStaticAttribute	Indicates that the value of a static field is unique for a particular context.
Convert	Converts a base data type to another base data type.
DataMisalignedException	The exception that is thrown when a unit of data is read from or written to an address that is not a multiple of the data size. This class cannot be inherited.
DBNull	Represents a nonexistent value. This class cannot be inherited.
Delegate	Represents a delegate, which is a data structure that refers to a static method or to a class instance and an instance method of that class.
DivideByZeroException	The exception that is thrown when there is an attempt to divide an integral or Decimal value by zero.
DllNotFoundException	The exception that is thrown when a DLL specified in a DLL import cannot be found.
DuplicateWaitObjectException	The exception that is thrown when an object appears more than once in an array of synchronization objects.
EntryPointNotFoundException	The exception that is thrown when an attempt to load a class fails due to the absence of an entry method.
Enum	Provides the base class for enumerations.
Environment	Provides information about, and means to manipulate, the current environment and platform. This class cannot be inherited.
EventArgs	Represents the base class for classes that contain event data, and provides a value to use for events that do not include event data.
Exception	Represents errors that occur during application execution.
ExecutionEngineException	The exception that is thrown when there is an internal error in the execution engine of the common language runtime. This class cannot be inherited.
FakeLoggerServiceProviderExtensions	Extensions for configuring fake logging, used in unit tests.
FakeRedactionServiceProviderExtensions	Extensions that allow registering a fake redactor in the application.
FieldAccessException	The exception that is thrown when there is an invalid attempt to access a private or protected field inside a class.
FileStyleUriParser	A customizable parser based on the File scheme.
FlagsAttribute	Indicates that an enumeration can be treated as a bit field; that is, a set of flags.