Code:
/ DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / Services / Monitoring / system / Diagnosticts / Stopwatch.cs / 1 / Stopwatch.cs
// ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== /*============================================================ ** ** Class: Stopwatch ** ** Purpose: Implementation for Stopwatch class. ** ** Date: Nov 27, 2002 ** ===========================================================*/ namespace System.Diagnostics { using Microsoft.Win32; using System; // This class uses high-resolution performance counter if installed hardware // does not support it. Otherwise, the class will fall back to DateTime class // and uses ticks as a measurement. public class Stopwatch { private const long TicksPerMillisecond = 10000; private const long TicksPerSecond = TicksPerMillisecond * 1000; private long elapsed; private long startTimeStamp; private bool isRunning; // "Frequency" stores the frequency of the high-resolution performance counter, // if one exists. Otherwise it will store TicksPerSecond. // The frequency cannot change while the system is running, // so we only need to initialize it once. public static readonly long Frequency; public static readonly bool IsHighResolution; // performance-counter frequency, in counts per ticks. // This can speed up conversion from high frequency performance-counter // to ticks. private static readonly double tickFrequency; static Stopwatch() { bool succeeded = SafeNativeMethods.QueryPerformanceFrequency(out Frequency); if(!succeeded) { IsHighResolution = false; Frequency = TicksPerSecond; tickFrequency = 1; } else { IsHighResolution = true; tickFrequency = TicksPerSecond; tickFrequency /= Frequency; } } public Stopwatch() { Reset(); } public void Start() { // Calling start on a running Stopwatch is a no-op. if(!isRunning) { startTimeStamp = GetTimestamp(); isRunning = true; } } public static Stopwatch StartNew() { Stopwatch s = new Stopwatch(); s.Start(); return s; } public void Stop() { // Calling stop on a stopped Stopwatch is a no-op. if( isRunning) { long endTimeStamp = GetTimestamp(); long elapsedThisPeriod = endTimeStamp - startTimeStamp; elapsed += elapsedThisPeriod; isRunning = false; } } public void Reset() { elapsed = 0; isRunning = false; startTimeStamp = 0; } public bool IsRunning { get { return isRunning; } } public TimeSpan Elapsed { get { return new TimeSpan( GetElapsedDateTimeTicks()); } } public long ElapsedMilliseconds { get { return GetElapsedDateTimeTicks()/TicksPerMillisecond; } } public long ElapsedTicks { get { return GetRawElapsedTicks(); } } public static long GetTimestamp() { if(IsHighResolution) { long timestamp = 0; SafeNativeMethods.QueryPerformanceCounter(out timestamp); return timestamp; } else { return DateTime.UtcNow.Ticks; } } // Get the elapsed ticks. private long GetRawElapsedTicks() { long timeElapsed = elapsed; if( isRunning) { // If the StopWatch is running, add elapsed time since // the Stopwatch is started last time. long currentTimeStamp = GetTimestamp(); long elapsedUntilNow = currentTimeStamp - startTimeStamp; timeElapsed += elapsedUntilNow; } return timeElapsed; } // Get the elapsed ticks. private long GetElapsedDateTimeTicks() { long rawTicks = GetRawElapsedTicks(); if( IsHighResolution) { // convert high resolution perf counter to DateTime ticks double dticks = rawTicks; dticks *= tickFrequency; return unchecked((long)dticks); } else { return rawTicks; } } } }
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- TreeViewHitTestInfo.cs
- UdpDiscoveryMessageFilter.cs
- SubpageParagraph.cs
- OleDbCommandBuilder.cs
- Calendar.cs
- DelegateCompletionCallbackWrapper.cs
- WindowsListViewItem.cs
- _NegoState.cs
- AnimatedTypeHelpers.cs
- FrameworkElementAutomationPeer.cs
- IpcServerChannel.cs
- Wildcard.cs
- SqlLiftIndependentRowExpressions.cs
- InteropAutomationProvider.cs
- FilteredReadOnlyMetadataCollection.cs
- sqlser.cs
- HtmlElementCollection.cs
- DataGridViewDesigner.cs
- DataGridViewTopLeftHeaderCell.cs
- ProtocolViolationException.cs
- DataServiceProviderWrapper.cs
- ConcurrentBag.cs
- SmtpNegotiateAuthenticationModule.cs
- OledbConnectionStringbuilder.cs
- ILGenerator.cs
- Listen.cs
- _ProxyChain.cs
- RuntimeArgument.cs
- ParallelEnumerable.cs
- DecodeHelper.cs
- IncrementalHitTester.cs
- ErasingStroke.cs
- SQLBytesStorage.cs
- ConstraintStruct.cs
- StaticResourceExtension.cs
- TemplateNameScope.cs
- SchemaNotation.cs
- TempFiles.cs
- EntitySetRetriever.cs
- OracleDataReader.cs
- ProjectedSlot.cs
- XmlDeclaration.cs
- SoapFormatterSinks.cs
- SchemaAttDef.cs
- ButtonAutomationPeer.cs
- XmlTextAttribute.cs
- SafePointer.cs
- HtmlElementErrorEventArgs.cs
- FormsAuthentication.cs
- ToolStripCustomTypeDescriptor.cs
- TransactionTraceIdentifier.cs
- MultiDataTrigger.cs
- ArrayElementGridEntry.cs
- PeerSecurityHelpers.cs
- WindowsListViewSubItem.cs
- Clause.cs
- WebPartAuthorizationEventArgs.cs
- FixUp.cs
- GetChildSubtree.cs
- Converter.cs
- DesignerAutoFormatStyle.cs
- FileDialog_Vista_Interop.cs
- RawStylusInput.cs
- FontStyleConverter.cs
- ManifestSignedXml.cs
- PropertyTab.cs
- DPAPIProtectedConfigurationProvider.cs
- AutomationPatternInfo.cs
- ApplicationBuildProvider.cs
- DesignerAutoFormatStyle.cs
- QilDataSource.cs
- Byte.cs
- GroupBoxDesigner.cs
- DispatcherHookEventArgs.cs
- TrackingParticipant.cs
- unsafenativemethodstextservices.cs
- TrackingLocationCollection.cs
- CssStyleCollection.cs
- MouseGesture.cs
- UiaCoreApi.cs
- GenericRootAutomationPeer.cs
- BulletedList.cs
- WindowExtensionMethods.cs
- embossbitmapeffect.cs
- ItemDragEvent.cs
- WebPartDescription.cs
- PartManifestEntry.cs
- CSharpCodeProvider.cs
- ComboBoxItem.cs
- TypeConverters.cs
- LongPath.cs
- DebugTraceHelper.cs
- KnownTypeAttribute.cs
- FixedSOMTableCell.cs
- PolyQuadraticBezierSegment.cs
- AccessDataSourceDesigner.cs
- HandledEventArgs.cs
- DateTimeEditor.cs
- OuterGlowBitmapEffect.cs
- MetaTable.cs