System.Diagnostics

The System.Diagnostics namespace provides classes that allow you to interact with system processes, event logs, and performance counters.

Remarks

The System.Diagnostics.EventLog component provides functionality to write to event logs, read event log entries, and create and delete event logs and event sources on the network. The System.Diagnostics.EntryWrittenEventHandler provides a way to interact with event logs asynchronously. Supporting classes provide access to more detailed control, including: permission restrictions, the ability to specify event log types (which controls the type of default data that is written with an event log entry), and iterate through collections of event log entries. For more information about these tasks, see the System.Diagnostics.EventLogPermission, System.Diagnostics.EventLogEntryType, and System.Diagnostics.EventLogEntryCollection classes.
The System.Diagnostics.Process class provides functionality to monitor system processes across the network, and to start and stop local system processes. In addition to retrieving lists of running processes (by specifying either the computer, the process name, or the process id) or viewing information about the process that currently has access to the processor, you can get detailed knowledge of process threads and modules both through the System.Diagnostics.Process class itself, and by interacting with the System.Diagnostics.ProcessThread and System.Diagnostics.ProcessModule classes. The System.Diagnostics.ProcessStartInfo class enables you to specify a variety of elements with which to start a new process, such as input, output, and error streams, working directories, and command line verbs and arguments. These give you fine control over the behavior of your processes. Other related classes let you specify window styles, process and thread priorities, and interact with collections of threads and modules.
The System.Diagnostics.PerformanceCounter class enables you to monitor system performance, while the System.Diagnostics.PerformanceCounterCategory class provides a way to create new custom counters and categories. You can write to local custom counters and read from both local and remote counters (system as well as custom). You can sample counters using the System.Diagnostics.PerformanceCounter class, and calculate results from successive performance counter samples using the System.Diagnostics.CounterSample class. The System.Diagnostics.CounterCreationData class enables you to create multiple counters in a category and specify their types. Other classes associated with the performance counter component provide access to collections of counters, counter permission, and counter types.

The System.Diagnostics namespace also provides classes that allow you to debug your application and to trace the execution of your code. For more information, see the System.Diagnostics.Trace and System.Diagnostics.Debug classes.

Classes

Type	Reason
BooleanSwitch	Provides a simple on/off switch that controls debugging and tracing output.
ConditionalAttribute	Indicates to compilers that a method call or attribute should be ignored unless a specified conditional compilation symbol is defined.
ConsoleTraceListener	Directs tracing or debugging output to either the standard output or the standard error stream.
CorrelationManager	Correlates traces that are part of a logical transaction.
CounterCreationData	Defines the counter type, name, and Help string for a custom counter.
CounterCreationDataCollection	Provides a strongly typed collection of System.Diagnostics.CounterCreationData objects.
CounterSample	Defines a structure that holds the raw data for a performance counter.
CounterSampleCalculator	Provides a set of utility functions for interpreting performance counter data.
DataReceivedEventArgs	Provides data for the System.Diagnostics.Process.OutputDataReceived and System.Diagnostics.Process.ErrorDataReceived events.
DataReceivedEventHandler	Represents the method that will handle the System.Diagnostics.Process.OutputDataReceived event or System.Diagnostics.Process.ErrorDataReceived event of a System.Diagnostics.Process.
Debug	Provides a set of methods and properties that help debug your code. This class cannot be inherited.
DebuggableAttribute	Modifies code generation for runtime just-in-time (JIT) debugging. This class cannot be inherited.
DebuggableAttribute+DebuggingModes	Documentation for this section has not yet been entered.
Debugger	Enables communication with a debugger. This class cannot be inherited.
DebuggerBrowsableAttribute	Determines if and how a member is displayed in the debugger variable windows. This class cannot be inherited.
DebuggerBrowsableState	Provides display instructions for the debugger.
DebuggerDisplayAttribute	Determines how a class or field is displayed in the debugger variable windows.
DebuggerHiddenAttribute	Specifies the System.Diagnostics.DebuggerHiddenAttribute. This class cannot be inherited.
DebuggerNonUserCodeAttribute	Identifies a type or member that is not part of the user code for an application.
DebuggerStepperBoundaryAttribute	Indicates the code following the attribute is to be executed in run, not step, mode.
DebuggerStepThroughAttribute	Instructs the debugger to step through the code instead of stepping into the code. This class cannot be inherited.
DebuggerTypeProxyAttribute	Specifies the display proxy for a type.
DebuggerVisualizerAttribute	Specifies that the type has a visualizer. This class cannot be inherited.
DefaultTraceListener	Provides the default output methods and behavior for tracing.
DelimitedListTraceListener	Directs tracing or debugging output to a text writer, such as a stream writer, or to a stream, such as a file stream.
DiagnosticsConfigurationHandler	Handles the diagnostics section of configuration files.
EntryWrittenEventArgs	Provides data for the System.Diagnostics.EventLog.EntryWritten event.
EntryWrittenEventHandler	Represents the method that will handle the System.Diagnostics.EventLog.EntryWritten event of an System.Diagnostics.EventLog.
EventInstance	Represents language-neutral information for an event log entry.
EventLog	Provides interaction with Windows event logs.
EventLogEntry	Encapsulates a single record in the event log. This class cannot be inherited.
EventLogEntryCollection	Defines size and enumerators for a collection of System.Diagnostics.EventLogEntry instances.
EventLogEntryType	Specifies the event type of an event log entry.
EventLogInstaller	Allows you to install and configure an event log that your application reads from or writes to when running.
EventLogPermission	Controls code access permissions for event logging.
EventLogPermissionAccess	Defines access levels used by System.Diagnostics.EventLog permission classes.
EventLogPermissionAttribute	Allows declaritive permission checks for event logging.
EventLogPermissionEntry	Defines the smallest unit of a code access security permission that is set for an System.Diagnostics.EventLog.
EventLogPermissionEntryCollection	Contains a strongly typed collection of System.Diagnostics.EventLogPermissionEntry objects.
EventLogTraceListener	Provides a simple listener that directs tracing or debugging output to an System.Diagnostics.EventLog.
EventSourceCreationData	Represents the configuration settings used to create an event log source on the local computer or a remote computer.
EventTypeFilter	Indicates whether a listener should trace based on the event type.
FileVersionInfo	Provides version information for a physical file on disk.
ICollectData	Prepares performance data for the performance DLL the system loads when working with performance counters.
InstanceData	Holds instance data associated with a performance counter sample.
InstanceDataCollection	Provides a strongly typed collection of System.Diagnostics.InstanceData objects.
InstanceDataCollectionCollection	Provides a strongly typed collection of System.Diagnostics.InstanceDataCollection objects.
MonitoringDescriptionAttribute	Specifies a description for a property or event.
OverflowAction	Specifies how to handle entries in an event log that has reached its maximum file size.
PerformanceCounter	Represents a Windows NT performance counter component.
PerformanceCounterCategory	Represents a performance object, which defines a category of performance counters.
PerformanceCounterCategoryType	Indicates whether the performance counter category can have multiple instances.
PerformanceCounterInstaller	Specifies an installer for the System.Diagnostics.PerformanceCounter component.
PerformanceCounterInstanceLifetime	Specifies the lifetime of a performance counter instance.
PerformanceCounterManager	Prepares performance data for the performance.dll the system loads when working with performance counters.
PerformanceCounterPermission	Allows control of code access permissions for System.Diagnostics.PerformanceCounter.
PerformanceCounterPermissionAccess	Defines access levels used by System.Diagnostics.PerformanceCounter permission classes.
PerformanceCounterPermissionAttribute	Allows declaritive performance counter permission checks.
PerformanceCounterPermissionEntry	Defines the smallest unit of a code access security permission that is set for a System.Diagnostics.PerformanceCounter.
PerformanceCounterPermissionEntryCollection	Contains a strongly typed collection of System.Diagnostics.PerformanceCounterPermissionEntry objects.
PerformanceCounterType	Specifies the formula used to calculate the System.Diagnostics.PerformanceCounter.NextValue method for a System.Diagnostics.PerformanceCounter instance.
Process	Provides access to local and remote processes and enables you to start and stop local system processes.
ProcessModule	Represents a.dll or .exe file that is loaded into a particular process.
ProcessModuleCollection	Provides a strongly typed collection of System.Diagnostics.ProcessModule objects.
ProcessPriorityClass	Indicates the priority that the system associates with a process. This value, together with the priority value of each thread of the process, determines each thread's base priority level.
ProcessStartInfo	Specifies a set of values that are used when you start a process.
ProcessThread	Represents an operating system process thread.
ProcessThreadCollection	Provides a strongly typed collection of System.Diagnostics.ProcessThread objects.
ProcessWindowStyle	Specified how a new window should appear when the system starts a process.
SourceFilter	Indicates whether a listener should trace a message based on the source of a trace.
SourceLevels	Specifies the levels of trace messages filtered by the source switch and event type filter.
SourceSwitch	Provides a multilevel switch to control tracing and debug output without recompiling your code.
StackFrame	Provides information about a System.Diagnostics.StackFrame, which represents a function call on the call stack for the current thread.
StackTrace	Represents a stack trace, which is an ordered collection of one or more stack frames.
Stopwatch	Provides a set of methods and properties that you can use to accurately measure elapsed time.
Switch	Provides an abstract base class to create new debugging and tracing switches.
SwitchAttribute	Identifies a switch used in an assembly, class, or member.
SwitchLevelAttribute	Identifies the level type for a switch.
TextWriterTraceListener	Directs tracing or debugging output to a System.IO.TextWriter or to a System.IO.Stream, such as System.IO.FileStream.
ThreadPriorityLevel	Specifies the priority level of a thread.
ThreadState	Specifies the current execution state of the thread.
ThreadWaitReason	Specifies the reason a thread is waiting.
Trace	Provides a set of methods and properties that help you trace the execution of your code. This class cannot be inherited.
TraceEventCache	Provides trace event data specific to a thread and a process.
TraceEventType	Identifies the type of event that has caused the trace.
TraceFilter	Provides the base class for trace filter implementations.
TraceLevel	Specifies what messages to output for the System.Diagnostics.Debug, System.Diagnostics.Trace and System.Diagnostics.TraceSwitch classes.
TraceListener	Provides the abstract base class for the listeners who monitor trace and debug output.
TraceListenerCollection	Provides a thread-safe list of System.Diagnostics.TraceListener objects.
TraceOptions	Specifies trace data options to be written to the trace output.
TraceSource	Provides a set of methods and properties that enable applications to trace the execution of code and associate trace messages with their source.
TraceSwitch	Provides a multilevel switch to control tracing and debug output without recompiling your code.
XmlWriterTraceListener	Directs tracing or debugging output as XML-encoded data to a System.IO.TextWriter or to a System.IO.Stream, such as a System.IO.FileStream.