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Question

I am writing this little login validation application as a step of my VBA learning process. The application should check whether the login name is "sa" and the password is "XEL". The application should allow the user to enter the username and password for a maximum of three times. If in the all of the three attempts, a wrong usename and password is entered, the application should display an error and close. And blow is my code:

Private Sub Command6_Click()
Me.Text0.SetFocus
cID = Text0.Text
Me.Text4.SetFocus
cPswd = Text4.Text

For i = 1 To 3
validpswd = False
If cID = "sa" And cPswd = "XEL" Then
validpswd = True
MsgBox "Successful"
Exit For
Else
MsgBox "Try again"
Exit For
End If
Next i
'MsgBox ("byebye")
'DoCmd.Close acForm, "Used Car Sales", acSaveYes

End Sub

Now it does the checking/validating part. But it doesn't do the three times max limitation, I am kind of confused as how to put the last message box code and close command into the whole code blocks. Any helps are appreciated.

Thank you very much.

Answer 1

What I see wrong is you are having them type in the username/password then click a button. That button then checks to see if the username/password matches the predefined values three times in a row. That is a problem because the user wouldn't be able to actually try three times.

To fix it, you create a Module/Form level variable and initialize it in the form load to 0. then you check in the button click if that variable is greater than 2. If it is, then you run your close procedure. If it isnt, then it checks your username and password to see if they are correct, if they aren't then it increments the Module level variable by 1. Example below.

EDIT: added a check since it doesn't quite catch it after the 3rd try. Feels a bit ugly, but it works.

EDIT2: Dyslexia moment, fixed the greater then, less then signs for the if statements and the associated values

Dim Tries as Long

Private Sub Form_Load()
Tries = 0

End Sub

Private Sub Command6_Click()
If Tries < 3 Then
    cID = Text0.Text
    cPswd = Text4.Text
    validpswd = False
    If cID = "sa" And cPswd = "XEL" Then
        validpswd = True
        MsgBox "Successful"
    Else
        Tries = Tries + 1
        If Tries > 2 Then
            MsgBox ("byebye")
            DoCmd.Close acForm, "Used Car Sales", acSaveYes
        else
        MsgBox "Try again"
        end if
    End If
    'MsgBox ("byebye")
    'DoCmd.Close acForm, "Used Car Sales", acSaveYes
End If
End Sub

Answer 2

Thanks all. This is what I did eventually. I am sure there is other better way to do this and please comment to let me know as well

If try < 3 Then


If cID <> "sa" Or cPswd <> "XEL" Then
try = try + 1
MsgBox "Try again"
Else
MsgBox "Successful"
try = 0
End If

If try = 3 Then
MsgBox ("Too many tries")
DoCmd.Close acForm, "Login Test", acSaveYes
End If

End If