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Пример свойства Value (Visual Basic)

В этом примере демонстрируется свойство Value с объектами Field и Property путем отображения значений полей и свойств для таблицы Employees .

'BeginValueVB  
Public Sub Main()  
    On Error GoTo ErrorHandler  
  
    'To integrate this code  
    'replace the data source and initial catalog values  
    'in the connection string  
  
    ' connection and recordset variables  
    Dim rstEmployees As ADODB.Recordset  
    Dim Cnxn As ADODB.Connection  
    Dim strCnxn As String  
    Dim strSQLEmployees As String  
     ' field property variables  
    Dim fld As ADODB.Field  
    Dim prp As ADODB.Property  
  
     ' Open connection  
    Set Cnxn = New ADODB.Connection  
    strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
    Cnxn.Open strCnxn  
  
    ' Open recordset with data from Employees table  
    Set rstEmployees = New ADODB.Recordset  
    strSQLEmployees = "employee"  
    rstEmployees.Open strSQLEmployees, Cnxn, , , adCmdTable  
    'rstEmployees.Open strSQLEmployees, Cnxn, adOpenStatic, adLockReadOnly, adCmdTable  
    ' the above two lines of code are identical  
  
    Debug.Print "Field values in rstEmployees"  
  
    ' Enumerate the Fields collection of the Employees table  
    For Each fld In rstEmployees.Fields  
        ' Because Value is the default property of a  
        ' Field object, the use of the actual keyword  
        ' here is optional.  
        Debug.Print "   " & fld.Name & " = " & fld.Value  
    Next fld  
  
    Debug.Print "Property values in rstEmployees"  
  
    ' Enumerate the Properties collection of the Recordset object  
    For Each prp In rstEmployees.Properties  
        Debug.Print "   " & prp.Name & " = " & prp.Value  
        ' because Value is the default property of a Property object  
        ' use of the actual Value keyword is optional  
    Next prp  
  
    ' 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  
'EndValueVB  

См. также:

Объект Field
Объект Property (ADO)
Свойство Value (ADO)