Exemplo da propriedade Count (VB)
Este exemplo demonstra a propriedade Count com duas coleções no banco de dados Employee. A propriedade obtém o número de objetos em cada coleção e define o limite superior para loops que enumeram essas coleções. Outra maneira de enumerar essas coleções sem usar a propriedade Count seria usando instruções For Each...Next
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'BeginCountVB
'To integrate this code
'replace the data source and initial catalog values
'in the connection string
Public Sub Main()
On Error GoTo ErrorHandler
' recordset and connection variables
Dim rstEmployees As ADODB.Recordset
Dim Cnxn As ADODB.Connection
Dim strSQLEmployees As String
Dim strCnxn As String
Dim intLoop As Integer
' Open a connection
Set Cnxn = New ADODB.Connection
strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _
"Initial Catalog='Northwind';Integrated Security='SSPI';"
Cnxn.Open strCnxn
' Open recordset with data from Employee table
Set rstEmployees = New ADODB.Recordset
strSQLEmployees = "Employee"
'rstEmployees.Open strSQLEmployee, Cnxn, , , adCmdTable
rstEmployees.Open strSQLEmployees, Cnxn, adOpenForwardOnly, adLockReadOnly, adCmdTable
'the above two lines opening the recordset are identical as
'the default values for CursorType and LockType arguments match those specified
' Print information about Fields collection
Debug.Print rstEmployees.Fields.Count & " Fields in Employee"
For intLoop = 0 To rstEmployees.Fields.Count - 1
Debug.Print " " & rstEmployees.Fields(intLoop).Name
Next intLoop
' Print information about Properties collection
Debug.Print rstEmployees.Properties.Count & " Properties in Employee"
For intLoop = 0 To rstEmployees.Properties.Count - 1
Debug.Print " " & rstEmployees.Properties(intLoop).Name
Next intLoop
' clean up
rstEmployees.Close
Cnxn.Close
Set rstEmployees = Nothing
Set Cnxn = Nothing
Exit Sub
ErrorHandler:
' clean up
If Not rstEmployees Is Nothing Then
If rstEmployees.State = adStateOpen Then rstEmployees.Close
End If
Set rstEmployees = Nothing
If Not Cnxn Is Nothing Then
If Cnxn.State = adStateOpen Then Cnxn.Close
End If
Set Cnxn = Nothing
If Err <> 0 Then
MsgBox Err.Source & "-->" & Err.Description, , "Error"
End If
End Sub
'EndCountVB