PRB: Masked Edit May Not Show Empty When Bound Field is Null

MORE INFORMATION

Steps to Reproduce Behavior

1. Create a new project. Add the Masked Edit Control to the project.
   
   NOTE: In Visual Basic 4.0, click Custom Controls on the Tools menu and check "Microsoft Masked Edit Control." In Visual Basic 5.0, click Components on the Project menu and check "Microsoft Masked Edit Control 5.0."
2. Add a Data Control to Form1.
3. Add a Masked Edit Control to Form1. Set the DataSource property to "Data1."
4. Add a Text Box to Form1. Set the DataSource property to "Data1."
5. Add the following code to Form1:

         Dim bFieldNull As Boolean
         Dim db As Database
         Dim rs As Recordset
   
         Private Sub Form_Load()
             'Create a table with a phone field. Put some records into it.
             'Some records will have a phone value, some will be empty
   
             Dim fd As Field
             Dim td As TableDef
             Dim i As Integer
   
             On Error GoTo myerr ' The next line will cause an error if the
                                 'database already exists
   
             'Create a database containing a table, "Table1", which contains
             'one field, "Phone".
             Set db = Workspaces(0).CreateDatabase("MaskTest", _
                 dbLangGeneral)
             Set td = db.CreateTableDef("Table1")
             Set fd = td.CreateField("Phone", dbText, 14)
             fd.AllowZeroLength = True
             td.Fields.Append fd
             db.TableDefs.Append td
   
             'Add data to the Phone Field for even number records. The Phone
             'Field for odd number records will remain null.
             Set rs = db.OpenRecordset("table1")
             For i = 1 To 6
                 rs.AddNew
                 If i Mod 2 = 0 Then
                     rs("phone") = "(234) 654-9876"
                 End If
                 rs.Update
             Next
   
             db.Close
             LoadTable 'Call the LoadTable sub
             Exit Sub
   
         myerr:
             LoadTable 'Call the LoadTable sub
         End Sub
   
         Private Sub LoadTable()
             'Set the Recordset for the Data Control to all the records
             'in Table1 and bind the Phone field to the Masked Edit control.
             Set db = DBEngine(0).OpenDatabase("MaskTest")
             Set rs = db.OpenRecordset("Table1")
             rs.MoveFirst
             Set Data1.Recordset = rs
             MaskEdBox1.Mask = "(###) ###-####"
             text1.DataField = "Phone"
             MaskEdBox1.DataField = "Phone"
         End Sub
   						

6. Press the F5 key to run the application.
7. Move through the records using the Data Control. Note that the Masked Edit Control does not update properly when the bound field is null. To work around this problem so that the Masked Edit control shows empty records when the bound field's value is null, add the code from the RESOLUTION section in this article to the Form1. Press the F5 key to run the application.