ACC: How to Create a Password Protected Form or Report

ID: Q179371


The information in this article applies to:


SUMMARY

Advanced: Requires expert coding, interoperability, and multiuser skills.

Microsoft Access has two built-in security features for protecting your database: User/Group accounts and permissions, and database passwords.

This article shows you how you can also set individual passwords for each form and report in your database.


MORE INFORMATION

Microsoft provides programming examples for illustration only, without warranty either expressed or implied, including, but not limited to, the implied warranties of merchantability and/or fitness for a particular purpose. This article assumes that you are familiar with the programming language being demonstrated and the tools used to create and debug procedures. Microsoft support professionals can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific needs. If you have limited programming experience, you may want to contact a Microsoft Certified Solution Provider or the Microsoft fee-based consulting line at (800) 936-5200. For more information about Microsoft Certified Solution Providers, please see the following page on the World Wide Web:

http://www.microsoft.com/mcsp/
For more information about the support options available from Microsoft, please see the following page on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp
By using code, you can prompt for a password when a user opens a form or a report. If the correct password is entered, the form or report is opened.

The following example shows you how you can password protect the Orders form in the sample database Northwind.mdb:

  1. Open the sample database Northwind.mdb.


  2. Create a module and type the following procedure:


  3. 
          Public Function KeyCode(Password As String) As Long
             ' This function will produce a unique key for the
             ' string that is passed in as the Password.
             Dim I As Integer
             Dim Hold As Long
    
             For I = 1 To Len(Password)
                Select Case (Asc(Left(Password, 1)) * I) Mod 4
                Case Is = 0
                   Hold = Hold + (Asc(Mid(Password, I, 1)) * I)
                Case Is = 1
                   Hold = Hold - (Asc(Mid(Password, I, 1)) * I)
                Case Is = 2
                   Hold = Hold + (Asc(Mid(Password, I, 1)) * _
                      (I - Asc(Mid(Password, I, 1))))
                Case Is = 3
                   Hold = Hold - (Asc(Mid(Password, I, 1)) * _
                      (I + Len(Password)))
             End Select
             Next I
             KeyCode = Hold
          End Function 
  4. Create a new table as follows:


  5. 
          Table: tblPassword
          ---------------------------
          Field Name: ObjectName
             Data Type: Text
             Field Size: 50
          Field Name: KeyCode
             Data Type: Number
             Field Size: Long Integer
             Input Mask: Password
    
          Table Properties: tblPassword
          -----------------------------
          PrimaryKey: ObjectName 
  6. Open the tblPassword table and enter the following data:


  7. 
          ObjectName: Orders
          KeyCode: 2818 
  8. Open the Orders form in Design view.


  9. Set the form's OnOpen property to the following event procedure:


  10. 
          Private Sub Form_Open(Cancel as Integer)
             Dim Hold As Variant
             Dim tmpKey As Long
             Dim I As Integer
             Dim rs As Recordset
             Dim db As Database
    
             On Error GoTo Error_Handler
             ' Check to see if the user is passing in the Password.
             If IsNull(Me.OpenArgs) Then
                Hold = InputBox("Please Enter Your Password", "Enter Password")
             Else
                Hold = Me.OpenArgs
             End If
             ' Open the table that contains the password.
             Set db = CurrentDb
             Set rs = db.OpenRecordset("tblPassword", dbOpenTable)
             rs.Index = "PrimaryKey"
             rs.Seek "=", Me.Name
             If rs.NoMatch Then
                MsgBox "Sorry cannot find password info. Please Try Again"
                Cancel = -1
             Else
                ' Test to see if the key generated matches the key in
                ' the table; if there is not a match, stop the form
                ' from opening.
                If Not (rs![keycode] = KeyCode(Cstr(Hold))) Then
                   MsgBox "Sorry you entered the wrong password.  " & _
                      "Please try again.", vbOKOnly, "Incorrect Password"
                   Cancel = -1
                End If
             End If
             rs.Close
             db.Close
             Exit Sub
    
          Error_Handler:
             MsgBox Err.Description, vbOKOnly, "Error #" & Err.Number
             Exit Sub
          End Sub 
  11. Close and save the Orders form.


  12. Open the Orders form and enter "PASSWORD" when prompted for a password. Note the Orders form opens.


  13. Close and reopen the Orders form and enter "PassWord" when prompted for a password.

    Note that you receive the message "Sorry you entered the wrong password. Please try again." and the Orders form does not open.


To determine what the corresponding KeyCode is for a given string, type the following into the Debug window and press ENTER:

?KeyCode("TestString") 
The above example returns 5864.

To hide the tblPassword table in the Database window, right-click on the tblPassowrd table and click Properties. In the properties window click the Hidden check box, and then click OK.

Additional query words: password-protected pass word


Keywords          : OffVBA FmsHowto PgmHowto ScrtOthr 
Version           : WINDOWS:7.0,97
Platform          : WINDOWS 
Issue type        : kbhowto 

Last Reviewed: July 6, 1999