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PIPointRecordedValuesByCountAsync Method

This method returns a specified number of compressed values beginning at the requested start time in the direction specified.

Namespace:  OSIsoft.AF.PI
Assembly:  OSIsoft.AFSDK (in OSIsoft.AFSDK.dll) Version:
public Task<AFValues> RecordedValuesByCountAsync(
	AFTime startTime,
	int count,
	bool forward,
	AFBoundaryType boundaryType,
	string filterExpression,
	bool includeFilteredValues,
	CancellationToken cancellationToken = null


Type: OSIsoft.AF.TimeAFTime
The start time of the request.
Type: SystemInt32
The number of compressed values to return. This number must be greater than zero.
Type: SystemBoolean
A value of indicates to begin at the start time and move forward in time. A value of indicates to move backward in time. When moving backward, values will be returned in time descending order.
Type: OSIsoft.AF.DataAFBoundaryType
A value from the AFBoundaryType enumeration that determines how the time and value at the start time is determined.
Type: SystemString
A filter expression that follows the performance equation syntax.
Type: SystemBoolean
Specify to indicate that values which fail the filter criteria are present in the returned data at the times where they occurred with a value set to a "Filtered" enumeration value with bad status. Repeated consecutive failures are omitted.
cancellationToken (Optional)
Type: System.ThreadingCancellationToken
A cancellation token used to abort processing before completion. Passing the default CancellationToken.None will run to completion or until the PIConnectionInfo.OperationTimeOut period elapses.

Return Value

Type: TaskAFValues
Returns a task whose result is an AFValues collection with the recorded values.
AggregateException Asynchronous methods throw AggregateException on failure which will contain one or more exceptions containing the failure.

Important note Important
Impersonation of AF SDK asynchronous calls relies on the .NET framework's built-in support for flowing execution context across asynchronous points. When making these calls while impersonating, the thread or runtime must be configured to propagate the impersonation across these asynchronous points (see the SecurityContext documentation for details).

Note Notes to Callers
This call might use a background task to complete some of its work. See the Threading Overview for some matters to consider when execution transitions to another thread.

Version Information


Supported in: 2.10.5, 2.10, 2.9.5, 2.9, 2.8.5, 2.8
See Also
Enabling Operational Intelligence