Stopwatch.GetTimestamp Método
Definição
Importante
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Obtém o número de tiques atual no mecanismo de temporizador.
public:
static long GetTimestamp();
public static long GetTimestamp ();
static member GetTimestamp : unit -> int64
Public Shared Function GetTimestamp () As Long
Retornos
Um inteiro longo que representa o valor do contador de tiques do mecanismo de temporizador subjacente.
Exemplos
O exemplo a seguir ilustra o uso do GetTimestamp método para atualizar um contador de desempenho.
#using <System.dll>
using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;
using namespace System::Diagnostics;
using namespace System::Runtime::InteropServices;
void OutputSample( CounterSample s )
{
Console::WriteLine( "\r\n+++++++++++" );
Console::WriteLine( "Sample values - \r\n" );
Console::WriteLine( " BaseValue = {0}", s.BaseValue );
Console::WriteLine( " CounterFrequency = {0}", s.CounterFrequency );
Console::WriteLine( " CounterTimeStamp = {0}", s.CounterTimeStamp );
Console::WriteLine( " CounterType = {0}", s.CounterType );
Console::WriteLine( " RawValue = {0}", s.RawValue );
Console::WriteLine( " SystemFrequency = {0}", s.SystemFrequency );
Console::WriteLine( " TimeStamp = {0}", s.TimeStamp );
Console::WriteLine( " TimeStamp100nSec = {0}", s.TimeStamp100nSec );
Console::WriteLine( "++++++++++++++++++++++" );
}
void CollectSamples()
{
String^ categoryName = "ElapsedTimeSampleCategory";
String^ counterName = "ElapsedTimeSample";
// Create the performance counter category.
if ( !PerformanceCounterCategory::Exists( categoryName ) )
{
CounterCreationDataCollection^ CCDC = gcnew CounterCreationDataCollection;
// Add the counter.
CounterCreationData^ ETimeData = gcnew CounterCreationData;
ETimeData->CounterType = PerformanceCounterType::ElapsedTime;
ETimeData->CounterName = counterName;
CCDC->Add( ETimeData );
// Create the category.
PerformanceCounterCategory::Create( categoryName,
"Demonstrates ElapsedTime performance counter usage.",
CCDC );
}
else
{
Console::WriteLine( "Category exists - {0}", categoryName );
}
// Create the performance counter.
PerformanceCounter^ PC = gcnew PerformanceCounter( categoryName,
counterName,
false );
// Initialize the counter.
PC->RawValue = Stopwatch::GetTimestamp();
DateTime Start = DateTime::Now;
// Loop for the samples.
for ( int j = 0; j < 100; j++ )
{
// Output the values.
if ( (j % 10) == 9 )
{
Console::WriteLine( "NextValue() = {0}", PC->NextValue() );
Console::WriteLine( "Actual elapsed time = {0}", DateTime::Now.Subtract( Start ) );
OutputSample( PC->NextSample() );
}
// Reset the counter on every 20th iteration.
if ( j % 20 == 0 )
{
PC->RawValue = Stopwatch::GetTimestamp();
Start = DateTime::Now;
}
System::Threading::Thread::Sleep( 50 );
}
Console::WriteLine( "Elapsed time = {0}", DateTime::Now.Subtract( Start ) );
}
int main()
{
CollectSamples();
}
using System;
using System.Collections;
using System.Collections.Specialized;
using System.Diagnostics;
using System.Runtime.InteropServices;
public class App
{
public static void Main()
{
CollectSamples();
}
public static void CollectSamples()
{
const String categoryName = "ElapsedTimeSampleCategory";
const String counterName = "ElapsedTimeSample";
// If the category does not exist, create the category and exit.
// Performance counters should not be created and immediately used.
// There is a latency time to enable the counters, they should be created
// prior to executing the application that uses the counters.
// Execute this sample a second time to use the category.
if ( !PerformanceCounterCategory.Exists(categoryName) )
{
CounterCreationDataCollection CCDC = new CounterCreationDataCollection();
// Add the counter.
CounterCreationData ETimeData = new CounterCreationData();
ETimeData.CounterType = PerformanceCounterType.ElapsedTime;
ETimeData.CounterName = counterName;
CCDC.Add(ETimeData);
// Create the category.
PerformanceCounterCategory.Create(categoryName,
"Demonstrates ElapsedTime performance counter usage.",
PerformanceCounterCategoryType.SingleInstance, CCDC);
// Return, rerun the application to make use of the new counters.
return;
}
else
{
Console.WriteLine("Category exists - {0}", categoryName);
}
// Create the performance counter.
PerformanceCounter PC = new PerformanceCounter(categoryName,
counterName,
false);
// Initialize the counter.
PC.RawValue = Stopwatch.GetTimestamp();
DateTime Start = DateTime.Now;
// Loop for the samples.
for (int j = 0; j < 100; j++)
{
// Output the values.
if ((j % 10) == 9)
{
Console.WriteLine("NextValue() = " + PC.NextValue().ToString());
Console.WriteLine("Actual elapsed time = " + DateTime.Now.Subtract(Start).ToString());
OutputSample(PC.NextSample());
}
// Reset the counter on every 20th iteration.
if (j % 20 == 0)
{
PC.RawValue = Stopwatch.GetTimestamp();
Start = DateTime.Now;
}
System.Threading.Thread.Sleep(50);
}
Console.WriteLine("Elapsed time = " + DateTime.Now.Subtract(Start).ToString());
}
private static void OutputSample(CounterSample s)
{
Console.WriteLine("\r\n+++++++++++");
Console.WriteLine("Sample values - \r\n");
Console.WriteLine(" BaseValue = " + s.BaseValue);
Console.WriteLine(" CounterFrequency = " + s.CounterFrequency);
Console.WriteLine(" CounterTimeStamp = " + s.CounterTimeStamp);
Console.WriteLine(" CounterType = " + s.CounterType);
Console.WriteLine(" RawValue = " + s.RawValue);
Console.WriteLine(" SystemFrequency = " + s.SystemFrequency);
Console.WriteLine(" TimeStamp = " + s.TimeStamp);
Console.WriteLine(" TimeStamp100nSec = " + s.TimeStamp100nSec);
Console.WriteLine("++++++++++++++++++++++");
}
}
Imports System.Collections
Imports System.Collections.Specialized
Imports System.Diagnostics
Imports System.Runtime.InteropServices
Public Class App
Public Shared Sub Main()
CollectSamples()
End Sub
Private Shared Sub CollectSamples()
Dim categoryName As String = "ElapsedTimeSampleCategory"
Dim counterName As String = "ElapsedTimeSample"
If Not PerformanceCounterCategory.Exists(categoryName) Then
Dim CCDC As New CounterCreationDataCollection()
' Add the counter.
Dim ETimeData As New CounterCreationData()
ETimeData.CounterType = PerformanceCounterType.ElapsedTime
ETimeData.CounterName = counterName
CCDC.Add(ETimeData)
' Create the category.
PerformanceCounterCategory.Create(categoryName, _
"Demonstrates ElapsedTime performance counter usage.", _
PerformanceCounterCategoryType.SingleInstance, CCDC)
Else
Console.WriteLine("Category exists - {0}", categoryName)
End If
' Create the counter.
Dim PC As PerformanceCounter
PC = New PerformanceCounter(categoryName, counterName, False)
' Initialize the counter.
PC.RawValue = Stopwatch.GetTimestamp()
Dim Start As DateTime = DateTime.Now
' Loop for the samples.
Dim j As Integer
For j = 0 To 99
' Output the values.
If j Mod 10 = 9 Then
Console.WriteLine(("NextValue() = " _
+ PC.NextValue().ToString()))
Console.WriteLine(("Actual elapsed time = " _
+ DateTime.Now.Subtract(Start).ToString()))
OutputSample(PC.NextSample())
End If
' Reset the counter every 20th iteration.
If j Mod 20 = 0 Then
PC.RawValue = Stopwatch.GetTimestamp()
Start = DateTime.Now
End If
System.Threading.Thread.Sleep(50)
Next j
Console.WriteLine(("Elapsed time = " + _
DateTime.Now.Subtract(Start).ToString()))
End Sub
Private Shared Sub OutputSample(ByVal s As CounterSample)
Console.WriteLine(ControlChars.Lf + ControlChars.Cr + "+++++++")
Console.WriteLine("Sample values - " + ControlChars.Cr _
+ ControlChars.Lf)
Console.WriteLine((" BaseValue = " _
+ s.BaseValue.ToString()))
Console.WriteLine((" CounterFrequency = " + _
s.CounterFrequency.ToString()))
Console.WriteLine((" CounterTimeStamp = " + _
s.CounterTimeStamp.ToString()))
Console.WriteLine((" CounterType = " + _
s.CounterType.ToString()))
Console.WriteLine((" RawValue = " + _
s.RawValue.ToString()))
Console.WriteLine((" SystemFrequency = " + _
s.SystemFrequency.ToString()))
Console.WriteLine((" TimeStamp = " + _
s.TimeStamp.ToString()))
Console.WriteLine((" TimeStamp100nSec = " + _
s.TimeStamp100nSec.ToString()))
Console.WriteLine("+++++++")
End Sub
End Class
Comentários
Se a Stopwatch classe usar um contador de desempenho de alta resolução, GetTimestamp retornará o valor atual desse contador. Se a Stopwatch classe usar o temporizador do sistema, GetTimestamp retornará a propriedade atual DateTime.Ticks da DateTime.UtcNow instância.