PerformanceCounter.NextValue-Methode
Ruft eine Zählermessung ab und gibt den dafür berechneten Wert zurück.
Namespace: System.Diagnostics
Assembly: System (in system.dll)
Syntax
'Declaration
Public Function NextValue As Single
'Usage
Dim instance As PerformanceCounter
Dim returnValue As Single
returnValue = instance.NextValue
public float NextValue ()
public:
float NextValue ()
public float NextValue ()
public function NextValue () : float
Rückgabewert
Der nächste berechnete Wert, den das System für diesen Zähler abruft.
Ausnahmen
| Ausnahmetyp | Bedingung |
|---|---|
Die Instanz ist keinem Leistungsindikator ordnungsgemäß zugeordnet. |
|
Fehler beim Zugriff auf eine System-API. |
|
Die Plattform ist Windows 98 oder Windows Millennium Edition (Me), die keine Leistungsindikatoren unterstützen. |
Hinweise
Hinweis
Wenn der berechnete Wert eines Zählers von zwei Zählerlesevorgängen abhängt, gibt der erste Lesevorgang 0,0 zurück.
Beispiel
Imports System
Imports System.Collections
Imports System.Collections.Specialized
Imports System.Diagnostics
Imports System.Runtime.InteropServices
Imports Microsoft.VisualBasic
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.", 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(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
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 ( !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.",
CCDC);
}
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("++++++++++++++++++++++");
}
}
#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();
}
import System.*;
import System.Collections.*;
import System.Collections.Specialized.*;
import System.Diagnostics.*;
import System.Runtime.InteropServices.*;
public class App
{
public static void main(String[] args)
{
CollectSamples();
} //main
public static void CollectSamples()
{
final String categoryName = "ElapsedTimeSampleCategory";
final String counterName = "ElapsedTimeSample";
if (!(PerformanceCounterCategory.Exists(categoryName))) {
CounterCreationDataCollection ccdc =
new CounterCreationDataCollection();
// Add the counter.
CounterCreationData eTimeData = new CounterCreationData();
eTimeData.set_CounterType(PerformanceCounterType.ElapsedTime);
eTimeData.set_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 = new PerformanceCounter(categoryName,
counterName, false);
// Initialize the counter.
pc.set_RawValue(Stopwatch.GetTimestamp());
DateTime start = DateTime.get_Now();
// Loop for the samples.
for (int j = 0; j < 100; j++) {
// Output the values.
if (j % 10 == 9) {
Console.WriteLine("NextValue() = " + ((Single)pc.NextValue()).
ToString());
Console.WriteLine("Actual elapsed time = "
+ DateTime.get_Now().Subtract(start).ToString());
OutputSample(pc.NextSample());
}
// Reset the counter on every 20th iteration.
if (j % 20 == 0) {
pc.set_RawValue(Stopwatch.GetTimestamp());
start = DateTime.get_Now();
}
System.Threading.Thread.Sleep(50);
}
Console.WriteLine("Elapsed time = " + DateTime.get_Now().
Subtract(start).ToString());
} //CollectSamples
private static void OutputSample(CounterSample s)
{
Console.WriteLine("\r\n+++++++++++");
Console.WriteLine("Sample values - \r\n");
Console.WriteLine(" BaseValue = " + s.get_BaseValue());
Console.WriteLine(" CounterFrequency = " + s.get_CounterFrequency());
Console.WriteLine(" CounterTimeStamp = " + s.get_CounterTimeStamp());
Console.WriteLine(" CounterType = " + s.get_CounterType());
Console.WriteLine(" RawValue = " + s.get_RawValue());
Console.WriteLine(" SystemFrequency = " + s.get_SystemFrequency());
Console.WriteLine(" TimeStamp = " + s.get_TimeStamp());
Console.WriteLine(" TimeStamp100nSec = " + s.get_TimeStamp100nSec());
Console.WriteLine("++++++++++++++++++++++");
} //OutputSample
} //App
.NET Framework-Sicherheit
- PerformanceCounterPermission zum Lesen der Leistungsindikatorkategorie. Zugeordnete Enumeration: PerformanceCounterPermissionAccess.Read
Plattformen
Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.
Versionsinformationen
.NET Framework
Unterstützt in: 2.0, 1.1, 1.0
Siehe auch
Referenz
PerformanceCounter-Klasse
PerformanceCounter-Member
System.Diagnostics-Namespace