Question

我对Visual Basic 6.0还是很陌生，但对它的了解却很少。我的项目是关于机场登机牌发生器。

在我的第一个表格中，我有一个文本框，供用户输入PNR。在此，程序必须搜索已存储在与ADODB连接的MS访问数据库中的PNR。如果用户输入的PNR正确，则必须转到下一张显示旅客和航班的完整详细信息的表格，否则应弹出一个味精。框中显示“无效的PNR”。

这是我在该程序中使用的编码：

Dim conn As ADODB.Connection
Dim RS As New ADODB.Recordset

Private Sub Form_Load()
Set conn = New ADODB.Connection
conn.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\16hu3a120(part2)\BOARDING PASS3.mdb;Persist Security Info=False"
conn.Open
conn.CursorLocation = adUseClient
RS.Open "select * from PID", conn, adOpenDynamic, adLockOptimistic
End Sub
Private Sub cmdcancel_Click(Index As Integer)
MsgBox "DO YOU WANT TO CANCEL THE PROCESS?", vbYesNoCancel
End
End Sub
Private Sub cmdconfirm_Click(Index As Integer)
Dim pnr As String
pnr = txtinput.Text
Do
    If (pnr = RS.Fields(0)) Then
    MsgBox "SUCCESSFUL"
    Form1.Show       
    ElseIf (pnr <> RS.Fields(0) & RS.EOF = True) Then
    MsgBox "Invalid PNR", vbRetryCancel
    RS.MoveFirst
    End
    Exit Do
    End If
    RS.MoveNext
Loop While RS.EOF = False
If pnr = "" Then
MsgBox " FIELDS CANNOT BE LEFT EMPTY", vbAbortRetryIgnore
End If
End
Exit Sub
End Sub

预先感谢

Answer 1

您的代码中有几个错误。

在“取消”按钮事件代码中，您需要处理消息框中的返回值并采取相应措施。

Private Sub cmdcancel_Click(sender As Object, e As EventArgs) Handles cmdCancel.Click
    '
    If MsgBox("DO YOU WANT TO CANCEL THE PROCESS?", vbYesNoCancel) <> vbNo Then
        'Hide the form and return to main window
        Me.Hide
    End If
    '
End Sub

在“确认”按钮事件代码中，您需要在处理输入之前（而不是在处理结束时）测试输入！

还需要简化操作顺序，以便以尽可能少的步骤/陈述来完成目标。

Private Sub cmdconfirm_Click(sender As Object, e As EventArgs) Handles cmdConfirm.Click
    '
    Dim matched as boolean
    Dim pnr As String
    pnr = txtinput.Text
    '
    If pnr = "" Then
        MsgBox("FIELDS CANNOT BE LEFT EMPTY", vbOkay)
    Else
        matched = false
        Do
            If (pnr = RS.Fields(0)) Then
                matched = True
                exit do
            End If
            RS.MoveNext
        Loop While RS.EOF = False
        '
        if matched Then
            MsgBox("SUCCESSFUL")
            Form1.Show
        Else
            MsgBox("Invalid PNR", vbOkay)
            'return to main form
            Me.Hide
        End If
    End If
    '
End Sub

最后，尽管我没有将其包含在代码中，但请务必丢弃创建和使用的变量，以避免内存泄漏！

vb6.0机场登机牌打印项目

1 个答案: