AFData.RecordedValuesByCount Method
- Last UpdatedNov 18, 2025
- 4 minute read
- PI System
- AF SDK 2024 R2
- Developer
This method returns a specified number of compressed values beginning at the requested start time in the direction specified.
Namespace: OSIsoft.AF.Data
Assembly: OSIsoft.AFSDK (in OSIsoft.AFSDK.dll) Version: 3.1.1.1182
Syntax
public AFValues RecordedValuesByCount( AFTime startTime, int count, bool forward, AFBoundaryType boundaryType, UOM desiredUOM, string filterExpression, bool includeFilteredValues )
Public Function RecordedValuesByCount ( startTime As AFTime, count As Integer, forward As Boolean, boundaryType As AFBoundaryType, desiredUOM As UOM, filterExpression As String, includeFilteredValues As Boolean ) As AFValues Dim instance As AFData Dim startTime As AFTime Dim count As Integer Dim forward As Boolean Dim boundaryType As AFBoundaryType Dim desiredUOM As UOM Dim filterExpression As String Dim includeFilteredValues As Boolean Dim returnValue As AFValues returnValue = instance.RecordedValuesByCount(startTime, count, forward, boundaryType, desiredUOM, filterExpression, includeFilteredValues)
public: AFValues^ RecordedValuesByCount( AFTime startTime, int count, bool forward, AFBoundaryType boundaryType, UOM^ desiredUOM, String^ filterExpression, bool includeFilteredValues )
member RecordedValuesByCount : startTime : AFTime * count : int * forward : bool * boundaryType : AFBoundaryType * desiredUOM : UOM * filterExpression : string * includeFilteredValues : bool -> AFValues
Parameters
- startTime
- Type: OSIsoft.AF.TimeAFTime
The start time of the request. - count
- Type: SystemInt32
The number of compressed values to return. This number must be greater than zero. - forward
- 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. - boundaryType
- Type: OSIsoft.AF.DataAFBoundaryType
A value from the AFBoundaryType enumeration that determines how the time and value at the start time is determined. - desiredUOM
- Type: OSIsoft.AF.UnitsOfMeasureUOM
The desired unit of measure for the returned values. If , then the values are returned in the unit of measure specified by the associated attribute's DefaultUOM property. - filterExpression
- Type: SystemString
A string containing a filter expression. Expression variables are relative to the attribute. Use '.' to reference the containing attribute. A or empty string indicates no filtering. If the attribute does not support the Filters option, the filter will be ignored. - includeFilteredValues
- 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.
Return Value
Type: AFValuesReturns an AFValues collection with the recorded values.
Exceptions
| Exception | Condition |
|---|---|
| NotSupportedException | The data reference does not support the this method, or the configured data reference does not support filter expressions and one was provided. |
| ArgumentException | The count is less than or equal to zero. |
Remarks
| This method, property, or class is not available in the legacy .NET 3.5 version of the SDK. |
| You must have ReadData security rights to read a data value. |