Delete 方法示例 (VB)
此示例使用 Delete 方法从 Recordset 中删除指定的记录。
'BeginDeleteVB
'To integrate this code
'replace the data source and initial catalog values
'in the connection string
Public Sub Main()
On Error GoTo ErrorHandler
Dim rstRoySched As ADODB.Recordset
Dim Cnxn As ADODB.Connection
Dim strCnxn As String
Dim strSQLRoySched As String
Dim strMsg As String
Dim strTitleID As String
Dim intLoRange As Integer
Dim intHiRange As Integer
Dim intRoyalty As Integer
' open connection
Set Cnxn = New ADODB.Connection
strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _
"Initial Catalog='Pubs';Integrated Security='SSPI';"
Cnxn.Open strCnxn
' open RoySched table with cursor client-side
Set rstRoySched = New ADODB.Recordset
rstRoySched.CursorLocation = adUseClient
rstRoySched.CursorType = adOpenStatic
rstRoySched.LockType = adLockBatchOptimistic
rstRoySched.Open "SELECT * FROM roysched WHERE royalty = 20", strCnxn, , , adCmdText
' Prompt for a record to delete
strMsg = "Before delete there are " & rstRoySched.RecordCount & _
" titles with 20 percent royalty:" & vbCr & vbCr
Do While Not rstRoySched.EOF
strMsg = strMsg & rstRoySched!title_id & vbCr
rstRoySched.MoveNext
Loop
strMsg = strMsg & vbCr & vbCr & "Enter the ID of a record to delete:"
strTitleID = UCase(InputBox(strMsg))
If strTitleID = "" Then
Err.Raise 1, , "You didn't enter any value for the record ID."
End If
' Move to the record and save data so it can be restored
rstRoySched.Filter = "title_id = '" & strTitleID & "'"
If rstRoySched.RecordCount < 1 Then
Err.Raise 1, , "There is no record for the record ID you entered."
End If
intLoRange = rstRoySched!lorange
intHiRange = rstRoySched!hirange
intRoyalty = rstRoySched!royalty
' Delete the record
rstRoySched.Delete
rstRoySched.UpdateBatch
' Show the results
rstRoySched.Filter = adFilterNone
rstRoySched.Requery
strMsg = ""
strMsg = "After delete there are " & rstRoySched.RecordCount & _
" titles with 20 percent royalty:" & vbCr & vbCr
Do While Not rstRoySched.EOF
strMsg = strMsg & rstRoySched!title_id & vbCr
rstRoySched.MoveNext
Loop
MsgBox strMsg
' Restore the data because this is a demonstration
rstRoySched.AddNew
rstRoySched!title_id = strTitleID
rstRoySched!lorange = intLoRange
rstRoySched!hirange = intHiRange
rstRoySched!royalty = intRoyalty
rstRoySched.UpdateBatch
' clean up
rstRoySched.Close
Set rstRoySched = Nothing
Exit Sub
ErrorHandler:
' clean up
If Not rstRoySched Is Nothing Then
If rstRoySched.State = adStateOpen Then rstRoySched.Close
End If
Set rstRoySched = Nothing
If Err <> 0 Then
MsgBox Err.Source & "-->" & Err.Description, , "Error"
End If
End Sub
'EndDeleteVB