Refresh 方法范例 (VB)

本范例演示使用 Refresh 方法来刷新存储过程 Command 对象的 Parameters 集合。

Public Sub RefreshX()

    Dim cnn1 As ADODB.Connection
    Dim cmdByRoyalty As ADODB.Command
    Dim rstByRoyalty As ADODB.Recordset
    Dim rstAuthors As ADODB.Recordset
    Dim intRoyalty As Integer
    Dim strAuthorID As String
    Dim strCnn As String

    ' Open connection.
    Set cnn1 = New ADODB.Connection
        strCnn = "Provider=sqloledb;" & _
        "Data Source=srv;Initial Catalog=Pubs;User Id=sa;Password=; "
    cnn1.Open strCnn
       
    ' Open a command object for a stored procedure
    ' with one parameter.
    Set cmdByRoyalty = New ADODB.Command
    Set cmdByRoyalty.ActiveConnection = cnn1
    cmdByRoyalty.CommandText = "byroyalty"
    cmdByRoyalty.CommandType = adCmdStoredProc
    cmdByRoyalty.Parameters.Refresh
   
    ' Get paramater value and execute the command,
    ' storing the results in a recordset.
    intRoyalty = Trim(InputBox("Enter royalty:"))
    cmdByRoyalty.Parameters(1) = intRoyalty
    Set rstByRoyalty = cmdByRoyalty.Execute()
       
    ' Open the Authors table to get author names for display.
    Set rstAuthors = New ADODB.Recordset
    rstAuthors.Open "Authors", cnn1, , , adCmdTable
   
    ' Print current data in the recordset, adding
    ' author names from Authors table.
    Debug.Print "Authors with " & intRoyalty & " percent royalty"
    Do While Not rstByRoyalty.EOF
        strAuthorID = rstByRoyalty!au_id
        Debug.Print "    " & rstByRoyalty!au_id & ", ";
        rstAuthors.Filter = "au_id = '" & strAuthorID & "'"
        Debug.Print rstAuthors!au_fname & " " & _
            rstAuthors!au_lname
        rstByRoyalty.MoveNext
    Loop

    rstByRoyalty.Close
    rstAuthors.Close
    cnn1.Close
   
End Sub