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ScriptBuffer Class

Serves as the base class for the read-only classes representing the input and the outputs that are generated by the Script component in the BufferWrapper project item in a Script component project.

Inheritance Hierarchy

System.Object
  Microsoft.SqlServer.Dts.Pipeline.ScriptBuffer

Namespace:  Microsoft.SqlServer.Dts.Pipeline
Assembly:  Microsoft.SqlServer.TxScript (in Microsoft.SqlServer.TxScript.dll)

Syntax

'Declaration
Public Class ScriptBuffer
'Usage
Dim instance As ScriptBuffer
public class ScriptBuffer
public ref class ScriptBuffer
type ScriptBuffer =  class end
public class ScriptBuffer

The ScriptBuffer type exposes the following members.

Constructors

  Name Description
Public method ScriptBuffer Initializes a new instance of the ScriptBuffer class.

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Properties

  Name Description
Protected property Item Gets or sets the value of a column in the buffer by using its index in the array of buffer column indexes.

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Methods

  Name Description
Protected method AddRow Adds an empty new row to the data flow buffer.
Protected method DirectRow Directs a row to the specified output when a component has more than one available output.
Protected method EndOfRowset Returns a value that indicates whether the end of the rows in a buffer has been reached.
Public method Equals (Inherited from Object.)
Protected method Finalize (Inherited from Object.)
Public method GetHashCode (Inherited from Object.)
Public method GetType (Inherited from Object.)
Protected method IsNull Returns a value that indicates whether the value of the specified column is nulla null reference (Nothing in Visual Basic).
Protected method MemberwiseClone (Inherited from Object.)
Protected method NextRow Tries to move to the next available row in the buffer and returns a value that indicates whether another row was available.
Protected method SetEndOfRowset Indicates to the data flow that no more rows will be added to the output buffer.
Protected method SetNull Makes the value of the specified column nulla null reference (Nothing in Visual Basic).
Public method ToString (Inherited from Object.)

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Fields

  Name Description
Protected field Buffer
Protected field BufferColumnIndexes An array of column indexes.

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Remarks

The ScriptBuffer class serves as the base class for the read-only classes representing the input and the outputs that are generated by the Script component in the BufferWrapper project item in a Script component project. The classes in the BufferWrapper project item provide the developer with a set of methods for working with the data flow buffers, as well as typed accessor properties for each column in the buffers.

The Script component developer does not use the ScriptBuffer class directly, but indirectly, through the derived classes in the BufferWrapper project item that represent the component's input and outputs.

For more information, see Coding and Debugging the Script Component and Understanding the Script Component Object Model.

Examples

The following code sample from Creating an Asynchronous Transformation with the Script Component demonstrates several methods and properties of the ScriptBuffer class, including AddRow, NextRow, EndOfRowset, and SetEndOfRowset.

Public Class ScriptMain
    Inherits UserComponent

    Private myRedmondAddressCount As Integer

    Public Overrides Sub CreateNewOutputRows()

        MySummaryOutputBuffer.AddRow()

    End Sub

    Public Overrides Sub MyAddressInput_ProcessInput(ByVal Buffer As MyAddressInputBuffer)

        While Buffer.NextRow()
            MyAddressInput_ProcessInputRow(Buffer)
        End While

        If Buffer.EndOfRowset Then
            MyAddressOutputBuffer.SetEndOfRowset()
            MySummaryOutputBuffer.MyRedmondCount = myRedmondAddressCount
            MySummaryOutputBuffer.SetEndOfRowset()
        End If

    End Sub

    Public Overrides Sub MyAddressInput_ProcessInputRow(ByVal Row As MyAddressInputBuffer)

        With MyAddressOutputBuffer
            .AddRow()
            .AddressID = Row.AddressID
            .City = Row.City
        End With

        If Row.City.ToUpper = "REDMOND" Then
            myRedmondAddressCount += 1
        End If

    End Sub

End Class

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.