Login Code

[choudhmh]

I have a problem; i know its a simple code but find it difficult to contruct the code.

I have two fields username and password. I need some code, when a user clicks the button event in the form it checks against the username and password in the table to see if its correct; if correct it let you login else a message box should show either the username or password is wrong.

Can someone give me a sniplet of the code that i could use.

Thanks

[MMcCarthy]

I have a problem; i know its a simple code but find it difficult to contruct the code.

I have two fields username and password. I need some code, when a user clicks the button event in the form it checks against the username and password in the table to see if its correct; if correct it let you login else a message box should show either the username or password is wrong.

Can someone give me a sniplet of the code that i could use.

Thanks

Put the following in the button click event. Assuming textbox on form for username is txtUser and for password is txtPass.

Dim password As String

If Not IsNull(Me.txtUser) Then
  password = DLookup("Password","tblUsers","[UserName]=" & Me.txtUser)
  If Not IsNull(password) Then
    If Not IsNull(Me.txtPass) Then
      If password = Me.txtPass
        'Code to Proceed goes here
      Else
        Msgbox "You have entered an incorrect password, please re-enter", vbOkOnly
        Exit Sub
      End If
    Else
      Msgbox "You must enter a password", vbOkOnly
      Exit Sub
    End If
  Else
    Msgbox "You have entered an incorrect username, please re-enter", vbOkOnly
  End if
Else
  Msgbox "You must enter a user name.", vbOKOnly
  Exit Sub
End If

Mary

[choudhmh]

I inserted this code in the button click event handler but keep on getting a command syntax error on If password = Me.txtPass.
at present my table has three field loginid, username and password. Do i have to specify the table through a select statement.

Private Sub go_Click()
On Error GoTo Err_go_Click
Screen.Previous Control.SetFocu s


Dim password As String

If Not IsNull(Me.txtUs er) Then
password = DLookup("Passwo rd", "tblUsers", "[UserName]=" & Me.txtUser)
If Not IsNull(password ) Then
If Not IsNull(Me.txtPa ss) Then
If password = Me.txtPass


Else
MsgBox "You have entered an incorrect password, please re-enter", vbOKOnly
Exit Sub
End If
Else
MsgBox "You must enter a password", vbOKOnly
Exit Sub
End If
Else
MsgBox "You have entered an incorrect username, please re-enter", vbOKOnly
End If
Else
MsgBox "You must enter a user name.", vbOKOnly
Exit Sub
End If
End Sub

Put the following in the button click event. Assuming textbox on form for username is txtUser and for password is txtPass.

Dim password As String

If Not IsNull(Me.txtUser) Then
   password = DLookup("Password","tblUsers","[UserName]=" & Me.txtUser)
   If Not IsNull(password) Then
	  If Not IsNull(Me.txtPass) Then
		 If password = Me.txtPass
			'Code to Proceed goes here
		 Else
			Msgbox "You have entered an incorrect password, please re-enter", vbOkOnly
			Exit Sub
		 End If
	  Else
		 Msgbox "You must enter a password", vbOkOnly
		 Exit Sub
	  End If
   Else
	  Msgbox "You have entered an incorrect username, please re-enter", vbOkOnly
   End if
Else
   Msgbox "You must enter a user name.", vbOKOnly
   Exit Sub
End If

Mary

[MMcCarthy]

I was only using these as an example as I didn't know what the textboxes on the form were called. Replace txtUser and txtPass with the name of the textboxes on the login form.

Private Sub go_Click()
On Error GoTo Err_go_Click
  Screen.PreviousControl.SetFocus
Dim password As String

If Not IsNull(Me.txtUser) Then
   password = DLookup("Password", "tblUsers", "[UserName]=" & Me.txtUser)
   If Not IsNull(password) Then
      If Not IsNull(Me.txtPass) Then
         If password = Me.txtPass
         
         
             Else
            MsgBox "You have entered an incorrect password, please re-enter", vbOKOnly
            Exit Sub
         End If
      Else
         MsgBox "You must enter a password", vbOKOnly
         Exit Sub
      End If
   Else
      MsgBox "You have entered an incorrect username, please re-enter", vbOKOnly
   End If
Else
   MsgBox "You must enter a user name.", vbOKOnly
   Exit Sub
End If
End Sub

[choudhmh]

I tried what you showed me, i still get the same error;

"compile error: Syntax Error" on If password = Me.txtPass

Not sure whats the problem. I've named my textboxes as txtUser & txtPass - but still get the error. Try on your one - i'm giving up on this now.

Thanks for your help

[MMcCarthy]

Add 'Then' to the end of the line

If password = Me.txtPass Then

[choudhmh]

now i get
run time error '94'
invalid use of null

[MMcCarthy]

Private Sub go_Click()
On Error GoTo Err_go_Click
  Screen.PreviousControl.SetFocus
Dim password As String

If Not IsNull(Me.txtUser) Then
   password = DLookup("Password", "tblUsers", "[UserName]=" & Me.txtUser)
   If Not IsNull(password) Then
      If Not IsNull(Me.txtPass) Then
         If password = Me.txtPass Then
           '**************** Your code here***********
         Else
            MsgBox "You have entered an incorrect password, please re-enter", vbOKOnly
            Exit Sub
         End If
      Else
         MsgBox "You must enter a password", vbOKOnly
         Exit Sub
      End If
   Else
      MsgBox "You have entered an incorrect username, please re-enter", vbOKOnly
   End If
Else
   MsgBox "You must enter a user name.", vbOKOnly
   Exit Sub
End If
End Sub

All possible nulls should be accounted for in the above code. What line exactly is your code stopping at.

Mary

[choudhmh]

The Null is stopping at:
password = DLookup("Passwo rd", "tblUsers", "[UserName]=" & Me.txtUser).

Also if i keep the:

On Error GoTo Err_go_Click
then i get this error: Label not defined.

If i delete that line then the null error comes in.

Thanks for all your help

[MMcCarthy]

Try changing password variable to a variant as follows:

Private Sub go_Click()
On Error GoTo Err_go_Click
  Screen.PreviousControl.SetFocus
Dim password As Variant

If Not IsNull(Me.txtUser) Then
   password = DLookup("Password", "tblUsers", "[UserName]=" & Me.txtUser)
   If Not IsNull(password) Then
      If Not IsNull(Me.txtPass) Then
         If password = Me.txtPass Then
           '**************** Your code here***********
         Else
            MsgBox "You have entered an incorrect password, please re-enter", vbOKOnly
            Exit Sub
         End If
      Else
         MsgBox "You must enter a password", vbOKOnly
         Exit Sub
      End If
   Else
      MsgBox "You have entered an incorrect username, please re-enter", vbOKOnly
   End If
Else
   MsgBox "You must enter a user name.", vbOKOnly
   Exit Sub
End If
End Sub