该范例使用 Supports 方法,显示用不同游标类型打开的记录集所支持的选项。运行该过程需要 DisplaySupport 过程。Public Sub SupportsX() Dim aintCursorType(4) As Integer Dim rstTitles As ADODB.Recordset Dim strCnn As String Dim intIndex As Integer ' 打开连接。 strCnn = "Provider=sqloledb;" & _ "Data Source=srv;Initial Catalog=pubs;User Id=sa;Password=; " ' 使用 CursorType 常量填充数组。 aintCursorType(0) = adOpenForwardOnly aintCursorType(1) = adOpenKeyset aintCursorType(2) = adOpenDynamic aintCursorType(3) = adOpenStatic
' 使用每个 CursorType 和优化锁定打开记录集, ' 然后调用 DisplaySupport 过程显示所支持的选项。 For intIndex = 0 To 3 Set rstTitles = New ADODB.Recordset rstTitles.CursorType = aintCursorType(intIndex) rstTitles.LockType = adLockOptimistic rstTitles.Open "titles", strCnn, , , adCmdTable
Select Case aintCursorType(intIndex) Case adOpenForwardOnly Debug.Print "ForwardOnly cursor supports:" Case adOpenKeyset Debug.Print "Keyset cursor supports:" Case adOpenDynamic Debug.Print "Dynamic cursor supports:" Case adOpenStatic Debug.Print "Static cursor supports:" End Select DisplaySupport rstTitles rstTitles.Close Next intIndexEnd SubPublic Sub DisplaySupport(rstTemp As ADODB.Recordset) Dim alngConstants(11) As Long Dim booSupports As Boolean Dim intIndex As Integer ' 用游标选项常量填充数组。 alngConstants(0) = adAddNew alngConstants(1) = adApproxPosition alngConstants(2) = adBook alngConstants(3) = adDelete alngConstants(4) = adFind alngConstants(5) = adHoldRecords alngConstants(6) = adMovePrevious alngConstants(7) = adNotify alngConstants(8) = adResync alngConstants(9) = adUpdate alngConstants(10) = adUpdateBatch
For intIndex = 0 To 10 booSupports = _ rstTemp.Supports(alngConstants(intIndex)) If booSupports Then Select Case alngConstants(intIndex) Case adAddNew Debug.Print " AddNew" Case adApproxPosition Debug.Print " AbsolutePosition and AbsolutePage" Case adBook Debug.Print " Book" Case adDelete Debug.Print " Delete" Case adFind Debug.Print " Find" Case adHoldRecords Debug.Print " Holding Records" Case adMovePrevious Debug.Print " MovePrevious and Move" Case adNotify Debug.Print " Notifications" Case adResync Debug.Print " Resyncing data" Case adUpdate Debug.Print " Update" Case adUpdateBatch Debug.Print " batch updating" End Select End If Next intIndexEnd Sub
Dim rstTitles As ADODB.Recordset
Dim strCnn As String
Dim intIndex As Integer ' 打开连接。
strCnn = "Provider=sqloledb;" & _
"Data Source=srv;Initial Catalog=pubs;User Id=sa;Password=; " ' 使用 CursorType 常量填充数组。
aintCursorType(0) = adOpenForwardOnly
aintCursorType(1) = adOpenKeyset
aintCursorType(2) = adOpenDynamic
aintCursorType(3) = adOpenStatic
' 使用每个 CursorType 和优化锁定打开记录集,
' 然后调用 DisplaySupport 过程显示所支持的选项。
For intIndex = 0 To 3
Set rstTitles = New ADODB.Recordset
rstTitles.CursorType = aintCursorType(intIndex)
rstTitles.LockType = adLockOptimistic
rstTitles.Open "titles", strCnn, , , adCmdTable
Select Case aintCursorType(intIndex)
Case adOpenForwardOnly
Debug.Print "ForwardOnly cursor supports:"
Case adOpenKeyset
Debug.Print "Keyset cursor supports:"
Case adOpenDynamic
Debug.Print "Dynamic cursor supports:"
Case adOpenStatic
Debug.Print "Static cursor supports:"
End Select DisplaySupport rstTitles
rstTitles.Close
Next intIndexEnd SubPublic Sub DisplaySupport(rstTemp As ADODB.Recordset) Dim alngConstants(11) As Long
Dim booSupports As Boolean
Dim intIndex As Integer ' 用游标选项常量填充数组。
alngConstants(0) = adAddNew
alngConstants(1) = adApproxPosition
alngConstants(2) = adBook
alngConstants(3) = adDelete
alngConstants(4) = adFind
alngConstants(5) = adHoldRecords
alngConstants(6) = adMovePrevious
alngConstants(7) = adNotify
alngConstants(8) = adResync
alngConstants(9) = adUpdate
alngConstants(10) = adUpdateBatch
For intIndex = 0 To 10
booSupports = _
rstTemp.Supports(alngConstants(intIndex))
If booSupports Then
Select Case alngConstants(intIndex)
Case adAddNew
Debug.Print " AddNew"
Case adApproxPosition
Debug.Print " AbsolutePosition and AbsolutePage"
Case adBook
Debug.Print " Book"
Case adDelete
Debug.Print " Delete"
Case adFind
Debug.Print " Find"
Case adHoldRecords
Debug.Print " Holding Records"
Case adMovePrevious
Debug.Print " MovePrevious and Move"
Case adNotify
Debug.Print " Notifications"
Case adResync
Debug.Print " Resyncing data"
Case adUpdate
Debug.Print " Update"
Case adUpdateBatch
Debug.Print " batch updating"
End Select
End If
Next intIndexEnd Sub