System.Runtime.CompilerServices Namespace

Provides functionality for compiler writers who use managed code to specify attributes in metadata that affect the run-time behavior of the common language runtime.

Classes

AccessedThroughPropertyAttribute	Specifies the name of the property that accesses the attributed field.
AsyncIteratorStateMachineAttribute	Indicates whether a method is an asynchronous iterator.
AsyncMethodBuilderAttribute	Indicates the type of the async method builder that should be used by a language compiler to build the attributed type when used as the return type of an async method.
AsyncStateMachineAttribute	Indicates whether a method is marked with either the Async or async modifier.
CallConvCdecl	Indicates that a method should use the Cdecl calling convention.
CallConvFastcall	This calling convention is not supported in this version of .NET.
CallConvMemberFunction	Indicates that the calling convention used is the member function variant.
CallConvStdcall	Indicates that a method should use the StdCall calling convention.
CallConvSuppressGCTransition	Indicates that a method should suppress the GC transition as part of the calling convention.
CallConvThiscall	Indicates that a method should use the ThisCall calling convention.
CallerArgumentExpressionAttribute	Indicates that a parameter captures the expression passed for another parameter as a string.
CallerFilePathAttribute	Allows you to obtain the full path of the source file that contains the caller. This is the file path at the time of compile.
CallerLineNumberAttribute	Allows you to obtain the line number in the source file at which the method is called.
CallerMemberNameAttribute	Allows you to obtain the method or property name of the caller to the method.
CallSite	A dynamic call site base class. This type is used as a parameter type to the dynamic site targets.
CallSite<T>	Dynamic site type.
CallSiteBinder	Class responsible for runtime binding of the dynamic operations on the dynamic call site.
CallSiteHelpers	Class that contains helper methods for DLR CallSites.
CollectionBuilderAttribute
CompilationRelaxationsAttribute	Controls the strictness of the code generated by the common language runtime's just-in-time (JIT) compiler.
CompilerFeatureRequiredAttribute	Indicates that compiler support for a particular feature is required for the location where this attribute is applied.
CompilerGeneratedAttribute	Distinguishes a compiler-generated element from a user-generated element. This class cannot be inherited.
CompilerGlobalScopeAttribute	Indicates that a class should be treated as if it has global scope.
CompilerMarshalOverride	Indicates that the modified instance of a variable differs from its true type when marshaling. This class cannot be inherited.
ConditionalWeakTable<TKey,TValue>	Enables compilers to dynamically attach object fields to managed objects.
ContractHelper	Provides methods that the binary rewriter uses to handle contract failures.
CppInlineNamespaceAttribute	Defines the inline namespace in C++/CLI.
CreateNewOnMetadataUpdateAttribute	Indicates a type should be replaced rather than updated when applying metadata updates.
CustomConstantAttribute	Defines a constant value that a compiler can persist for a field or method parameter.
DateTimeConstantAttribute	Persists an 8-byte DateTime constant for a field or parameter.
DebugInfoGenerator	Generates debug information for lambda expressions in an expression tree.
DecimalConstantAttribute	Stores the value of a Decimal constant in metadata. This class cannot be inherited.
DefaultDependencyAttribute	Provides a hint to the common language runtime (CLR) indicating how likely a dependency is to be loaded. This class is used in a dependent assembly to indicate what hint should be used when the parent does not specify the DependencyAttribute attribute. This class cannot be inherited.
DependencyAttribute	Indicates when a dependency is to be loaded by the referring assembly. This class cannot be inherited.
DisablePrivateReflectionAttribute	Indicates that any private members contained in an assembly's types are not available to reflection.
DisableRuntimeMarshallingAttribute	Disables the built-in runtime managed/unmanaged marshalling subsystem for P/Invokes, Delegate types, and unmanaged function pointer invocations.
DiscardableAttribute	Marks a type definition as discardable.
DynamicAttribute	Indicates that the use of Object on a member is meant to be treated as a dynamically dispatched type.
EnumeratorCancellationAttribute	Allows users of async-enumerable methods to mark the parameter that should receive the cancellation token value from GetAsyncEnumerator(CancellationToken).
ExtensionAttribute	Indicates that a method is an extension method, or that a class or assembly contains extension methods.
FixedAddressValueTypeAttribute	Fixes the address of a static value type field throughout its lifetime. This class cannot be inherited.
FixedBufferAttribute	Indicates that a field should be treated as containing a fixed number of elements of the specified primitive type. This class cannot be inherited.
FormattableStringFactory	Provides a static method to create a FormattableString object from a composite format string and its arguments.
HasCopySemanticsAttribute	This class is obsolete. This class cannot be inherited.
IDispatchConstantAttribute	Indicates that the default value for the attributed field or parameter is an instance of DispatchWrapper, where the WrappedObject is null.
IndexerNameAttribute	Indicates the name by which an indexer is known in programming languages that do not support indexers directly.
InlineArrayAttribute	Indicates that the instance's storage is sequentially replicated Length times.
InternalsVisibleToAttribute	Specifies that types that are ordinarily visible only within the current assembly are visible to a specified assembly.
InterpolatedStringHandlerArgumentAttribute	Indicates which arguments to a method involving an interpolated string handler should be passed to that handler.
InterpolatedStringHandlerAttribute	Indicates the attributed type is to be used as an interpolated string handler.
IsBoxed	Indicates that the modified reference type is a boxed value type. This class cannot be inherited.
IsByRefLikeAttribute	Indicates that a structure is byref-like.
IsByValue	Indicates that a modified method argument should be interpreted as having object passed-by-value semantics. This modifier is applied to reference types. This class cannot be inherited.
IsConst	Indicates that the modified type has a const modifier. This class cannot be inherited.
IsCopyConstructed	Indicates that any copying of values of this type must use the copy constructor provided by the type. This class cannot be inherited.
IsExplicitlyDereferenced	Indicates that a managed pointer represents a pointer parameter within a method signature. This class cannot be inherited.
IsExternalInit	Reserved to be used by the compiler for tracking metadata. This class should not be used by developers in source code.
IsImplicitlyDereferenced	Indicates that the modified garbage collection reference represents a reference parameter within a method signature. This class cannot be inherited.
IsJitIntrinsic	Indicates that a modified method is an intrinsic value for which the just-in-time (JIT) compiler can perform special code generation. This class cannot be inherited.
IsLong	Indicates that a modified integer is a standard C++ long value. This class cannot be inherited.
IsPinned	Indicates that a modified instance is pinned in memory. This class cannot be inherited.
IsReadOnlyAttribute	Marks a program element as read-only.
IsSignUnspecifiedByte	Indicates that a modifier is neither signed nor unsigned. This class cannot be inherited.
IsUdtReturn	Indicates that a return type is a user-defined type. This class cannot be inherited.
IsUnmanagedAttribute	Reserved for use by a compiler for tracking metadata. This attribute should not be used by developers in source code.
IsVolatile	Marks a field as volatile. This class cannot be inherited.
IteratorStateMachineAttribute	Indicates whether a method in Visual Basic is marked with the Iterator modifier.
IUnknownConstantAttribute	Indicates that the default value for the attributed field or parameter is an instance of UnknownWrapper, where the WrappedObject is null. This class cannot be inherited.
MetadataUpdateOriginalTypeAttribute	Emitted by the compiler when a type that's marked with CreateNewOnMetadataUpdateAttribute is updated during a hot reload session.
MethodImplAttribute	Specifies the details of how a method is implemented. This class cannot be inherited.
ModuleInitializerAttribute	Used to indicate to the compiler that a method should be called in its containing module's initializer.
NativeCppClassAttribute	Applies metadata to an assembly that indicates that a type is an unmanaged type. This class cannot be inherited.
NullableAttribute	Reserved for use by a compiler for tracking metadata. This attribute should not be used by developers in source code.
NullableContextAttribute	Reserved for use by a compiler for tracking metadata. This attribute should not be used by developers in source code.
NullablePublicOnlyAttribute	Reserved for use by a compiler for tracking metadata. This attribute should not be used by developers in source code.
PreserveBaseOverridesAttribute	Ensures that any virtual call to the method, whether it uses the base signature or derived signature of the method, executes the most derived override.
ReadOnlyCollectionBuilder<T>	The builder for read only collection.
ReferenceAssemblyAttribute	Identifies an assembly as a reference assembly, which contains metadata but no executable code.
RefSafetyRulesAttribute	Indicates the language version of the ref safety rules used when the module was compiled.
RequiredAttributeAttribute	Specifies that an importing compiler must fully understand the semantics of a type definition, or refuse to use it. This class cannot be inherited.
RequiredMemberAttribute	Specifies that a type has required members or that a member is required.
RequiresLocationAttribute	Reserved for use by a compiler for tracking metadata. This attribute should not be used by developers in source code.
RuleCache<T>	Represents a cache of runtime binding rules.
RuntimeCompatibilityAttribute	Specifies whether to wrap exceptions that do not derive from the Exception class with a RuntimeWrappedException object. This class cannot be inherited.
RuntimeFeature	Defines APIs to determine whether specific features are supported by the common language runtime.
RuntimeHelpers	Provides a set of static methods and properties that provide support for compilers. This class cannot be inherited.
RuntimeWrappedException	Wraps an exception that does not derive from the Exception class. This class cannot be inherited.
ScopedRefAttribute	Reserved for use by a compiler for tracking metadata. This attribute should not be used by developers in source code.
ScopelessEnumAttribute	Indicates that a native enumeration is not qualified by the enumeration type name. This class cannot be inherited.
SkipLocalsInitAttribute	Indicates to the compiler that the .locals init flag should not be set in nested method headers when emitting to metadata.
SpecialNameAttribute	Indicates that a type or member is treated in a special way by the runtime or tools. This class cannot be inherited.
StateMachineAttribute	Allows you to determine whether a method is a state machine method.
StringFreezingAttribute	Deprecated. Freezes a string literal when creating native images using the Ngen.exe (Native Image Generator). This class cannot be inherited.
StrongBox<T>	Holds a reference to a value.
SuppressIldasmAttribute	Prevents the Ildasm.exe (IL Disassembler) from disassembling an assembly. This class cannot be inherited.
SwitchExpressionException	Indicates that a switch expression that was non-exhaustive failed to match its input at runtime. The exception optionally contains an object representing the unmatched value.
TupleElementNamesAttribute	Indicates that the use of a value tuple on a member is meant to be treated as a tuple with element names.
TypeForwardedFromAttribute	Specifies a source Type in another assembly.
TypeForwardedToAttribute	Specifies a destination Type in another assembly.
Unsafe	Contains generic, low-level functionality for manipulating managed and unmanaged pointers.
UnsafeAccessorAttribute	Provides access to an inaccessible member of a specific type.
UnsafeValueTypeAttribute	Specifies that a type contains an unmanaged array that might potentially overflow. This class cannot be inherited.

Structs

AsyncIteratorMethodBuilder	Represents a builder for asynchronous iterators.
AsyncTaskMethodBuilder	Represents a builder for asynchronous methods that return a task.
AsyncTaskMethodBuilder<TResult>	Represents a builder for asynchronous methods that returns a task and provides a parameter for the result.
AsyncValueTaskMethodBuilder	Represents a builder for asynchronous methods that return a ValueTask.
AsyncValueTaskMethodBuilder<TResult>	Represents a builder for asynchronous methods that returns a ValueTask<TResult>.
AsyncVoidMethodBuilder	Represents a builder for asynchronous methods that do not return a value.
ConfiguredAsyncDisposable	Provides a type that can be used to configure how awaits on an IAsyncDisposable are performed.
ConfiguredCancelableAsyncEnumerable<T>.Enumerator	Provides an awaitable async enumerator that enables cancelable iteration and configured awaits.
ConfiguredCancelableAsyncEnumerable<T>	Provides an awaitable async enumerable that enables cancelable iteration and configured awaits.
ConfiguredTaskAwaitable	Provides an awaitable object that enables configured awaits on a task.
ConfiguredTaskAwaitable.ConfiguredTaskAwaiter	Provides an awaiter for an awaitable (ConfiguredTaskAwaitable) object.
ConfiguredTaskAwaitable<TResult>.ConfiguredTaskAwaiter	Provides an awaiter for an awaitable object(ConfiguredTaskAwaitable<TResult>).
ConfiguredTaskAwaitable<TResult>	Provides an awaitable object that enables configured awaits on a task.
ConfiguredValueTaskAwaitable	Provides an awaitable type that enables configured awaits on a ValueTask.
ConfiguredValueTaskAwaitable.ConfiguredValueTaskAwaiter	Provides an awaiter for a ConfiguredValueTaskAwaitable.
ConfiguredValueTaskAwaitable<TResult>.ConfiguredValueTaskAwaiter	Provides an awaiter for a ConfiguredValueTaskAwaitable<TResult>.
ConfiguredValueTaskAwaitable<TResult>	Provides an awaitable type that enables configured awaits on a ValueTask<TResult>.
DefaultInterpolatedStringHandler	Provides a handler used by the language compiler to process interpolated strings into String instances.
PoolingAsyncValueTaskMethodBuilder	Represents a builder for asynchronous methods that return a ValueTask.
PoolingAsyncValueTaskMethodBuilder<TResult>	Represents a builder for asynchronous methods that returns a ValueTask<TResult>.
TaskAwaiter	Provides an object that waits for the completion of an asynchronous task.
TaskAwaiter<TResult>	Represents an object that waits for the completion of an asynchronous task and provides a parameter for the result.
ValueTaskAwaiter	Provides an awaiter for a ValueTask.
ValueTaskAwaiter<TResult>	Provides an awaiter for a ValueTask<TResult>.
YieldAwaitable	Provides the context for waiting when asynchronously switching into a target environment.
YieldAwaitable.YieldAwaiter	Provides an awaiter for switching into a target environment.

Interfaces

IAsyncStateMachine	Represents state machines that are generated for asynchronous methods. This type is intended for compiler use only.
ICriticalNotifyCompletion	Represents an awaiter that schedules continuations when an await operation completes.
INotifyCompletion	Represents an operation that schedules continuations when it completes.
IRuntimeVariables	Represents the values of run-time variables.
IStrongBox	Defines a property for accessing the value that an object references.
ITuple	Defines a general-purpose Tuple implementation that allows access to Tuple instance members without knowing the underlying Tuple type.

Enums

CompilationRelaxations	Specifies parameters that control the strictness of the code generated by the common language runtime's just-in-time (JIT) compiler.
LoadHint	Specifies the preferred default binding for a dependent assembly.
MethodCodeType	Defines how a method is implemented.
MethodImplOptions	Specifies constants that define the details of how a method is implemented.
UnsafeAccessorKind	Specifies the kind of target to which an UnsafeAccessorAttribute is providing access.

Delegates

ConditionalWeakTable<TKey,TValue>.CreateValueCallback	Represents a method that creates a non-default value to add as part of a key/value pair to a ConditionalWeakTable<TKey,TValue> object.
RuntimeHelpers.CleanupCode	Represents a method to run when an exception occurs.
RuntimeHelpers.TryCode	Represents a delegate to code that should be run in a try block.

Remarks

This namespace is primarily for compiler writers, although several of its classes, such as InternalsVisibleToAttribute, are used in a wide variety of applications.