System Namespace

The exception that is thrown when there is an attempt to read or write protected memory.

Identifies the activation context for the current application. This class cannot be inherited.

Contains methods to create types of objects locally or remotely, or obtain references to existing remote objects. This class cannot be inherited.

Represents one or more errors that occur during application execution.

Provides members for setting and retrieving data about an application's context.

Represents an application domain, which is an isolated environment where applications execute. This class cannot be inherited.

Provides a managed equivalent of an unmanaged host.

Represents assembly binding information that can be added to an instance of AppDomain.

The exception that is thrown when an attempt is made to access an unloaded application domain.

Serves as the base class for application-defined exceptions.

Contains information used to uniquely identify a manifest-based application. This class cannot be inherited.

Provides the ability to uniquely identify a manifest-activated application. This class cannot be inherited.

The exception that is thrown when one of the arguments provided to a method is not valid.

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.

The exception that is thrown when the value of an argument is outside the allowable range of values as defined by the invoked method.

The exception that is thrown for errors in an arithmetic, casting, or conversion operation.

Provides methods for creating, manipulating, searching, and sorting arrays, thereby serving as the base class for all arrays in the common language runtime.

The exception that is thrown when an attempt is made to store an element of the wrong type within an array.

Provides data for the AssemblyLoad event.

Represents the base class for custom attributes.

Specifies the usage of another attribute class. This class cannot be inherited.

The exception that is thrown when the file image of a dynamic link library (DLL) or an executable program is invalid.

Converts base data types to an array of bytes, and an array of bytes to base data types.

Manipulates arrays of primitive types.

The exception that is thrown when an attempt to unload an application domain fails.

Supports iterating over a String object and reading its individual characters. This class cannot be inherited.

Indicates whether a program element is compliant with the Common Language Specification (CLS). This class cannot be inherited.

Represents the standard input, output, and error streams for console applications. This class cannot be inherited.

Provides data for the CancelKeyPress event. This class cannot be inherited.

Defines the base class for all context-bound classes.

The exception that is thrown when an attempt to marshal an object across a context boundary fails.

Indicates that the value of a static field is unique for a particular context.

Converts a base data type to another base data type.

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.

Represents a nonexistent value. This class cannot be inherited.

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.

The exception that is thrown when there is an attempt to divide an integral or Decimal value by zero.

The exception that is thrown when a DLL specified in a DLL import cannot be found.

The exception that is thrown when an object appears more than once in an array of synchronization objects.

The exception that is thrown when an attempt to load a class fails due to the absence of an entry method.

Provides the base class for enumerations.

Provides information about, and means to manipulate, the current environment and platform. This class cannot be inherited.

Represents the base class for classes that contain event data, and provides a value to use for events that do not include event data.

Represents errors that occur during application execution.

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.

The exception that is thrown when there is an invalid attempt to access a private or protected field inside a class.

A customizable parser based on the File scheme.

Indicates that an enumeration can be treated as a bit field; that is, a set of flags.

The exception that is thrown when the format of an argument is invalid, or when a composite format string is not well formed.

Represents a composite format string, along with the arguments to be formatted.

A customizable parser based on the File Transfer Protocol (FTP) scheme.

Controls the system garbage collector, a service that automatically reclaims unused memory.

A customizable parser for a hierarchical URI.

A customizable parser based on the Gopher scheme.

A customizable parser based on the HTTP scheme.

The exception that is thrown when an attempt is made to access an element of an array or collection with an index that is outside its bounds.

The exception that is thrown when there is insufficient execution stack available to allow most methods to execute.

The exception that is thrown when a check for sufficient available memory fails. This class cannot be inherited.

The exception that is thrown for invalid casting or explicit conversion.

The exception that is thrown when a method call is invalid for the object's current state.

The exception that is thrown when a program contains invalid Microsoft intermediate language (MSIL) or metadata. Generally this indicates a bug in the compiler that generated the program.

The exception that is thrown when time zone information is invalid.

Provides support for lazy initialization.

Provides a lazy indirect reference to an object and its associated metadata for use by the Managed Extensibility Framework.

A customizable parser based on the Lightweight Directory Access Protocol (LDAP) scheme.

Used to set the default loader optimization policy for the main method of an executable application.

Encapsulates a memory slot to store local data. This class cannot be inherited.

Enables access to objects across application domain boundaries in applications that support remoting.

Provides constants and static methods for trigonometric, logarithmic, and other common mathematical functions.

Provides constants and static methods for trigonometric, logarithmic, and other common mathematical functions.

The exception that is thrown when an attempt to access a class member fails.

Provides extension methods for for the memory- and span-related types, such as Memory<T>, ReadOnlyMemory<T>, Span<T>, and ReadOnlySpan<T>.

The exception that is thrown when there is an invalid attempt to access a method, such as accessing a private method from partially trusted code.

The exception that is thrown when there is an attempt to dynamically access a field that does not exist. If a field in a class library has been removed or renamed, recompile any assemblies that reference that library.

The exception that is thrown when there is an attempt to dynamically access a class member that does not exist or that is not declared as public. If a member in a class library has been removed or renamed, recompile any assemblies that reference that library.

The exception that is thrown when there is an attempt to dynamically access a method that does not exist.

Indicates that the COM threading model for an application is multithreaded apartment (MTA).

Represents a multicast delegate; that is, a delegate that can have more than one element in its invocation list.

The exception that is thrown when there is an attempt to combine two delegates based on the Delegate type instead of the MulticastDelegate type. This class cannot be inherited.

A parser based on the NetPipe scheme for the "Indigo" system.

A parser based on the NetTcp scheme for the "Indigo" system.

A customizable parser based on the news scheme using the Network News Transfer Protocol (NNTP).

Indicates that a field of a serializable class should not be serialized. This class cannot be inherited.

The exception that is thrown when a floating-point value is positive infinity, negative infinity, or Not-a-Number (NaN).

The exception that is thrown when a requested method or operation is not implemented.

The exception that is thrown when an invoked method is not supported, or when there is an attempt to read, seek, or write to a stream that does not support the invoked functionality.

Supports a value type that can be assigned null. This class cannot be inherited.

The exception that is thrown when there is an attempt to dereference a null object reference.

Supports all classes in the .NET class hierarchy and provides low-level services to derived classes. This is the ultimate base class of all .NET classes; it is the root of the type hierarchy.

The exception that is thrown when an operation is performed on a disposed object.

Marks the program elements that are no longer in use. This class cannot be inherited.

Represents information about an operating system, such as the version and platform identifier. This class cannot be inherited.

The exception that is thrown in a thread upon cancellation of an operation that the thread was executing.

The exception that is thrown when there is not enough memory to continue the execution of a program.

The exception that is thrown when an arithmetic, casting, or conversion operation in a checked context results in an overflow.

Indicates that a method will allow a variable number of arguments in its invocation. This class cannot be inherited.

The exception that is thrown when a feature does not run on a particular platform.

Provides an IProgress<T> that invokes callbacks for each reported progress value.

Represents a pseudo-random number generator, which is an algorithm that produces a sequence of numbers that meet certain statistical requirements for randomness.

The exception that is thrown when an array with the wrong number of dimensions is passed to a method.

Provides data for loader resolution events, such as the TypeResolve, ResourceResolve, ReflectionOnlyAssemblyResolve, and AssemblyResolve events.

Indicates that a class can be serialized. This class cannot be inherited.

The exception that is thrown when the execution stack overflows because it contains too many nested method calls. This class cannot be inherited.

Indicates that the COM threading model for an application is single-threaded apartment (STA).

Represents text as a sequence of UTF-16 code units.

Represents a string comparison operation that uses specific case and culture-based or ordinal comparison rules.

Provides extension methods to work with string normalization.

Serves as the base class for system exceptions namespace.

Indicates that the value of a static field is unique for each thread.

The exception that is thrown when the time allotted for a process or operation has expired.

Represents a time zone.

Represents any time zone in the world.

Provides information about a time zone adjustment, such as the transition to and from daylight saving time.

The exception that is thrown when a time zone cannot be found.

Provides static methods for creating tuple objects.

Represents a 1-tuple, or singleton.

Represents a 2-tuple, or pair.

Represents a 3-tuple, or triple.

Represents a 4-tuple, or quadruple.

Represents a 5-tuple, or quintuple.

Represents a 6-tuple, or sextuple.

Represents a 7-tuple, or septuple.

Represents an n-tuple, where n is 8 or greater.

Provides extension methods for tuples to interoperate with language support for tuples in C#.

Represents type declarations: class types, interface types, array types, value types, enumeration types, type parameters, generic type definitions, and open or closed constructed generic types.

The exception that is thrown when a method attempts to use a type that it does not have access to.

The exception that is thrown as a wrapper around the exception thrown by the class initializer. This class cannot be inherited.

The exception that is thrown when type-loading failures occur.

The exception that is thrown when there is an attempt to access an unloaded class.

The exception that is thrown when the operating system denies access because of an I/O error or a specific type of security error.

Provides data for the event that is raised when there is an exception that is not handled in any application domain.

Provides an object representation of a uniform resource identifier (URI) and easy access to the parts of the URI.

Provides a custom constructor for uniform resource identifiers (URIs) and modifies URIs for the Uri class.

The exception that is thrown when an invalid Uniform Resource Identifier (URI) is detected.

Parses a new URI scheme. This is an abstract class.

A class that represents a Uniform Resource Identifier (URI) template.

A class used to compare UriTemplate instances for structural (instead of reference) equivalence.

A class that represents the results of a match operation on a UriTemplate instance.

Represents an error when matching a Uri to a UriTemplateTable.

A class that represents an associative set of UriTemplate objects.

Converts a String type to a Uri type, and vice versa.

Provides the base class for value types.

Represents the version number of an assembly, operating system, or the common language runtime. This class cannot be inherited.

Represents a weak reference, which references an object while still allowing that object to be reclaimed by garbage collection.

Represents a typed weak reference, which references an object while still allowing that object to be reclaimed by garbage collection.

Provides extension methods for converting between tasks and Windows Runtime asynchronous actions and operations.

Represents a variable-length argument list; that is, the parameters of a function that takes a variable number of arguments.

Provides an enumerator for the elements of an ArraySegment<T>.

Delimits a section of a one-dimensional array.

Represents a Boolean (true or false) value.

Represents an 8-bit unsigned integer.

Represents a character as a UTF-16 code unit.

Describes the console key that was pressed, including the character represented by the console key and the state of the SHIFT, ALT, and CTRL modifier keys.

Represents an instant in time, typically expressed as a date and time of day.

Represents a point in time, typically expressed as a date and time of day, relative to Coordinated Universal Time (UTC).

Represents a decimal floating-point number.

Represents a double-precision floating-point number.

Represents the size and the fragmenation of a generation on entry and on exit of the GC reported in GCMemoryInfo.

Provides a set of APIs that can be used to retrieve garbage collection information.

Represents a globally unique identifier (GUID).

An IEEE 754 compliant float16 type.

Combines the hash code for multiple values into a single hash code.

Represents a type that can be used to index a collection either from the start or the end.

Represents a 16-bit signed integer.

Represents a 32-bit signed integer.

Represents a 64-bit signed integer.

A platform-specific type that is used to represent a pointer or a handle.

Represents a contiguous region of memory.

Represents a runtime handle for a module.

Represents a value type that can be assigned null.

Represents a range that has start and end indexes.

Represents a contiguous region of memory, similar to ReadOnlySpan<T>. Unlike ReadOnlySpan<T>, it is not a byref-like type.

Provides an enumerator for the elements of a ReadOnlySpan<T>.

Provides a type-safe and memory-safe read-only representation of a contiguous region of arbitrary memory.

References a variable-length argument list.

Represents a field using an internal metadata token.

RuntimeMethodHandle is a handle to the internal metadata representation of a method.

Represents a type using an internal metadata token.

Represents an 8-bit signed integer.

Represents a position in a non-contiguous set of memory. Properties of this type should not be interpreted by anything but the type that created it.

Represents a single-precision floating-point number.

Provides an enumerator for the elements of a Span<T>.

Provides a type- and memory-safe representation of a contiguous region of arbitrary memory.

Represents a time interval.

Provides information about a specific time change, such as the change from daylight saving time to standard time or vice versa, in a particular time zone.

Describes objects that contain both a managed pointer to a location and a runtime representation of the type that may be stored at that location.

Represents a 16-bit unsigned integer.

Represents a 32-bit unsigned integer.

Represents a 64-bit unsigned integer.

A platform-specific type that is used to represent a pointer or a handle.

Provides static methods for creating value tuples.

Represents a value tuple with a single component.

Represents a value tuple with 2 components.

Represents a value tuple with 3 components.

Represents a value tuple with 4 components.

Represents a value tuple with 5 components.

Represents a value tuple with 6 components.

Represents a value tuple with 7 components.

Represents an n-value tuple, where n is 8 or greater.

Specifies a return value type for a method that does not return a value.

Exposes the public members of the AppDomain class to unmanaged code.

Represents assembly binding information that can be added to an instance of AppDomain.

Provides a mechanism for releasing unmanaged resources asynchronously.

Represents the status of an asynchronous operation.

Supports cloning, which creates a new instance of a class with the same value as an existing instance.

Defines a generalized type-specific comparison method that a value type or class implements to order or sort its instances.

Defines a generalized comparison method that a value type or class implements to create a type-specific comparison method for ordering or sorting its instances.

Defines methods that convert the value of the implementing reference or value type to a common language runtime type that has an equivalent value.

Defines a method that supports custom formatting of the value of an object.

Provides a mechanism for releasing unmanaged resources.

Defines a generalized method that a value type or class implements to create a type-specific method for determining equality of instances.

Provides a mechanism for retrieving an object to control formatting.

Provides functionality to format the value of an object into a string representation.

Defines a provider for push-based notification.

Provides a mechanism for receiving push-based notifications.

Defines a provider for progress updates.

Defines a mechanism for retrieving a service object; that is, an object that provides custom support to other objects.

Indicates the context for a manifest-activated application.

Specifies the action that a custom application domain manager takes when initializing a new domain.

Specifies the application elements on which it is valid to apply an attribute.

Specifies whether relevant ToBase64CharArray and ToBase64String methods insert line breaks in their output.

Specifies constants that define foreground and background colors for the console.

Specifies the standard keys on a console.

Represents the SHIFT, ALT, and CTRL modifier keys on a keyboard.

Specifies combinations of modifier and console keys that can interrupt the current process.

Specifies whether a DateTime object represents a local time, a Coordinated Universal Time (UTC), or is not specified as either local time or UTC.

Specifies the day of the week.

Specifies enumerated constants used to retrieve directory paths to system special folders.

Specifies options to use for getting the path to a special folder.

Specifies the location where an environment variable is stored or retrieved in a set or get operation.

Specifies the behavior for a forced garbage collection.

Specifies the kind of a garbage collection.

Provides information about the current registration for notification of the next full garbage collection.

Specifies options for a UriParser.

An enumeration used with the LoaderOptimizationAttribute class to specify loader optimizations for an executable.

Specifies how mathematical rounding methods should process a number that is midway between two numbers.

Identifies the operating system, or platform, supported by an assembly.

Specifies the culture, case, and sort rules to be used by certain overloads of the Compare(String, String) and Equals(Object) methods.

Specifies options for applicable Split method overloads, such as whether to omit empty substrings from the returned array or trim whitespace from substrings.

Specifies the type of an object.

Specifies the parts of a Uri.

Controls how URI information is escaped.

Defines host name types for the CheckHostName(String) method.

Provides the possible values for the configuration setting of the IdnElement in the System.Configuration namespace.

Defines the different kinds of URIs.

Defines the parts of a URI for the GetLeftPart(UriPartial) method.

Encapsulates a method that has no parameters and does not return a value.

Encapsulates a method that has a single parameter and does not return a value.

Encapsulates a method that has two parameters and does not return a value.

Encapsulates a method that has three parameters and does not return a value.

Encapsulates a method that has four parameters and does not return a value.

Encapsulates a method that has five parameters and does not return a value.

Encapsulates a method that has six parameters and does not return a value.

Encapsulates a method that has seven parameters and does not return a value.

Encapsulates a method that has eight parameters and does not return a value.

Encapsulates a method that has nine parameters and does not return a value.

Encapsulates a method that has 10 parameters and does not return a value.

Encapsulates a method that has 11 parameters and does not return a value.

Encapsulates a method that has 12 parameters and does not return a value.

Encapsulates a method that has 13 parameters and does not return a value.

Encapsulates a method that has 14 parameters and does not return a value.

Encapsulates a method that has 15 parameters and does not return a value.

Encapsulates a method that has 16 parameters and does not return a value.

Represents the callback method to invoke when the application domain is initialized.

Represents the method that handles the AssemblyLoad event of an AppDomain.

References a method to be called when a corresponding asynchronous operation completes.

Represents the method that compares two objects of the same type.

Represents the method that will handle the CancelKeyPress event of a Console.

Represents a method that converts an object from one type to another type.

Used by DoCallBack(CrossAppDomainDelegate) for cross-application domain calls.

Represents the method that will handle an event that has no event data.

Represents the method that will handle an event when the event provides data.

Encapsulates a method that has no parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has one parameter and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has two parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has three parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has four parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has five parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has six parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has seven parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has eight parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has nine parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 10 parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 11 parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 12 parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 13 parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 14 parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 15 parameters and returns a value of the type specified by the TResult parameter.

Encapsulates a method that has 16 parameters and returns a value of the type specified by the TResult parameter.

Represents the method that defines a set of criteria and determines whether the specified object meets those criteria.

Represents a method that handles the TypeResolve, ResourceResolve, or AssemblyResolve event of an AppDomain.

Represents the method that will handle the event raised by an exception that is not handled by the application domain.