This class represents a
Windows NT, 2000, or XP
performance counter that can be accessed using the Performance
Administrative Tool. PerformanceCounters already
exist for system devices, such as processor, disk, or memory usage,
as well as for system resources, such as processes or threads. Using
the PerformanceCounter class, you can both read
from and write performance data to existing custom counters.
To create your own custom performance counters, use
PerformanceCounterCategory.Create( ). You can
write to a performance counter by using one of the
PerformanceCounter constructors that takes the
boolean readonly argument. Set that argument to
false to create a performance counter that you can
write to. To set the value of a performance counter, call
IncrementBy( ), Increment( ),
or Decrement( ), or set the
RawValue to the desired value.
To access an existing performance counter, create an instance of
PerformanceCounter with the
CategoryName and CounterName
set to that of an available category and an existing performance
counter. The category and counter names are case-insensitive, so you
could sample the available memory by calling the constructor as
PerformanceCounter("memory", "available
mbytes"). Consult the Performance Administrative Tool for
the available performance counters. You can explicitly set the
CategoryName and CounterName
(and the optional InstanceName and
MachineName) properties, if you choose not to set
these using the constructor.
To obtain a new data sample for a counter, call either
NextValue( ) or NextSample( ).
NextSample( ) returns a
CounterSample structure that represents the raw
captured performance data. NextValue( ) fetches
the next sample and calculates its value based on the raw data it
contains. To permanently remove a counter, call
RemoveInstance( ). If you attempt to modify or
remove a counter in which the ReadOnly property is
set to true, an
InvalidOperationException is returned.
public sealed class PerformanceCounter : System.ComponentModel.Component,
System.ComponentModel.ISupportInitialize {
// Public Constructors
public PerformanceCounter( );
public PerformanceCounter(string categoryName, string counterName);
public PerformanceCounter(string categoryName, string counterName, bool readOnly);
public PerformanceCounter(string categoryName, string counterName, string instanceName);
public PerformanceCounter(string categoryName, string counterName, string instanceName,
bool readOnly);
public PerformanceCounter(string categoryName, string counterName, string instanceName,
string machineName);
// Public Static Fields
public static int DefaultFileMappingSize;
// =524288
// Public Instance Properties
public string CategoryName{set; get; }
public string CounterHelp{get; }
public string CounterName{set; get; }
public PerformanceCounterType CounterType{get; }
public string InstanceName{set; get; }
public string MachineName{set; get; }
public long RawValue{set; get; }
public bool ReadOnly{set; get; }
// Public Static Methods
public static void CloseSharedResources( );
// Public Instance Methods
public void BeginInit( );
// implements System.ComponentModel.ISupportInitialize
public void Close( );
public long Decrement( );
public void EndInit( );
// implements System.ComponentModel.ISupportInitialize
public long Increment( );
public long IncrementBy(long value);
public CounterSample NextSample( );
public float NextValue( );
public void RemoveInstance( );
// Protected Instance Methods
protected override void Dispose(bool disposing);
// overrides System.ComponentModel.Component
}
System.MarshalByRefObject