ACC2000: How to Manipulate ZIP Codes in Microsoft Access

You can manipulate ZIP codes in Microsoft Access by changing the data type, input mask, or format of a ZIP code field. This article shows you how to manipulate ZIP codes that are already stored in a table and how to format ZIP codes when you enter them on a form.

This article contains the following sections:

• Creating the PostalCodeExample Table Used in this Article
• Restoring Leading Zeros That Are Missing
• Saving Formatted ZIP Codes
• Removing Trailing Hyphens from Existing ZIP Codes
• Inserting Hyphens in Existing Nine-Digit (ZIP+4) ZIP Codes
• Formatting ZIP Codes for Use in Reports or Other Applications

Creating the PostalCodeExample Table Used in This Article

1. Start Microsoft Access, and then create a new blank database.
2. In the Database dialog box, double-click Create table in Design view, and then create the following table:
   Table: PostalCodeExample
   Field Name: PCode
   Data Type: Text
3. Close the table, click Yes to save the table, and then in the Save As dialog box, enter PostalCodeExample. Do not create a primary key.

Restoring Leading Zeros That Are Missing

Store ZIP codes in a Text field in your table rather than in a Number field. Microsoft Access follows standard mathematical conventions when storing numeric data, so if you enter a ZIP code that contains leading zeros in a Number field, Microsoft Access removes the leading zeros when you save the data. For example, if you enter 01002 in a Number field, Microsoft Access stores the number as 1002.

To restore leading zeros to ZIP codes that have been stored in a Number field, follow these steps:

1. In the Database dialog box, under Objects, click Tables.
2. Click PostalCodeExample table, and then click Open. Enter the following five- and nine-digit ZIP code records:
   00345
   023456789
3. On the View menu, click Design View.
4. Change the data type of the PCode field to Number, and set the FieldSize property to Long Integer.
5. Save the table, and then on the View menu click Datasheet View. Note that the leading zeros have been removed.
6. On the View menu, click Design View and return the data type of the PCode field to Text so that it can store the restored leading zeros in your ZIP codes. Save the table.
7. Create the following update query based on the PostalCodeExample table.
   Query Name: RestoreLeadingZeros
   Query Type: Update Query
   
   Field: PCode
   Table: PostalCodeExample
   Update To: IIf(Len([PCode])<6, Format([PCode],"00000"), _
        Format([PCode],"000000000"))
8. Run the query and confirm the update when prompted. Open the PostalCodeExample table. Note that the leading zeros have been restored.

Saving Formatted ZIP Codes

The Input Mask Wizard helps you to create an input mask for ZIP codes that stores a hyphen after the fifth digit as a literal character. However, when the hyphen is stored as a literal character, it is saved in all ZIP codes, whether it is a five-digit or nine-digit code. The U.S. Postal Service will accept ZIP codes with trailing hyphens, but you may want to avoid trailing hyphens for aesthetic reasons.

If you omit the input mask, you can avoid trailing hyphens in your 5-digit ZIP codes. Then you can either manually include the hyphen when you enter nine-digit (ZIP+4) ZIP codes, or you can use a form to programmatically insert the hyphen after a nine-digit (ZIP+4) ZIP code has been entered. In either case, you also gain the ability to enter foreign postal codes in your table.

To create a form that will programmatically insert a hyphen when a nine-digit (ZIP+4) ZIP Code is entered, follow these steps:

1. Create a new form based on the PostalCodeExample table using the AutoForm: Columnar Wizard.
2. Save the form as frmFormatZIP, and then on the View menu click Design View.
3. On the View menu, click Code.
4. Type the following line in the Declarations section of the form's class module sheet:

   Dim mvarZip
   					

5. Type the following procedures:

   Private Sub PCode_AfterUpdate()
      If IsEmpty(mvarZip) Then Exit Sub
      If Len(mvarZip) = 6 Then
         Screen.ActiveControl = Left(mvarZip, Len(mvarZip)-1)
      Else
         Screen.ActiveControl = Format(mvarZip, "@@@@@-@@@@")
      End If
      mvarZip = Empty
   End Sub
   
   Private Sub PCode_BeforeUpdate(Cancel As Integer)
      Dim ctlZip As Control
      Dim strTitle As String
      Dim strMsg As String
      Const cYesNoButtons = 4
      Const cNoChosen = 7
   
      mvarZip = Empty
      Set ctlZip = Screen.ActiveControl
   
      If ctlZip Like "#####-####" Or ctlZip Like "#####" Then
         Exit Sub
      ElseIf ctlZip Like "#########" Or ctlZip Like "#####-" Then
         mvarZip = ctlZip
      Else
         strTitle = "Not a ZIP Code."
         strMsg = "Save as entered?"
         If MsgBox(strMsg, cYesNoButtons, strTitle) = cNoChosen Then
            Cancel = True
         End If
      End If
   End Sub
   					

6. On the File menu, click Close and Return to Microsoft Access.
7. On the View menu, click Form View, and then add the following new records:
   01234
   987651011
   WA1 1DP
   1010
   NOTE: When you enter WA1 1DP and 1010, and are prompted to save the ZIP codes as entered, click Yes.
8. Save and close the form, and then open the PostalCodeExample table. Note that the five-digit ZIP code you entered does not contain a hyphen, the nine-digit ZIP code you entered does contain a hyphen, and the other two records you entered are stored as entered.

Removing Trailing Hyphens from Existing ZIP Codes

You can use an update query to remove trailing hyphens from existing ZIP codes. Follow these steps to remove the trailing hyphens:

1. Open the PostalCodeExample table and enter the following records:
   12345-
   987654321
   12345-6789
2. Create the following update query based on the PostalCodeExample table:
   Query Name: RemoveTrailingHyphens
   Query Type: Update Query
   
   Field: [PCode] Like "#####-"
   Criteria: True
   
   Field: PCode
   Table: PostalCodeExample
   Update To: Left([PCode], Len([PCode])-1)
3. Run the query and confirm the update when prompted.
4. Open the PostalCodeExample table. Note that the trailing hyphen after "12345" has been removed.

Inserting hyphens in Existing Nine-Digit (ZIP+4) ZIP Codes

You can use an update query to insert missing hyphens in nine-digit ZIP codes. Follow these steps to insert a hyphen in nine-digit ZIP codes:

1. Open the PostalCodeExample table and enter the following records:
   12345
   987654321
   12345-6789
2. Create the following update query based on the PostalCodeExample table:
   Query Name: InsertHyphens
   Query Type: Update Query
   
   Field: [PCode] Like "#########"
   Criteria: True
   
   Field: PCode
   Update To: Format([PCode],"@@@@@-@@@@")
3. Run the query and confirm the update when prompted.
4. Open the PostalCodeExample table. Note that the nine-digit (ZIP+4) ZIP codes all contain hyphens after the fifth digit.

Formatting ZIP Codes for Use in Reports or Other Applications

You can use your ZIP codes in a Microsoft Access report or in another application (such as Microsoft Word) without modification if they already are saved in the desired format. Earlier sections in this article demonstrate how to change the way your existing ZIP code formats are stored in the table. However, if you want to format ZIP codes without changing the way they are stored, you can follow these steps to temporarily create the ZIP code format you want to use.

1. Open the PostalCodeExample table, and then enter the following records:
   54321
   12345-
   987654321
   12345-6789
2. Create the following query based on the PostalCodeExample table.
   
   NOTE: In this example, the underscore (_) at the end of the Field line is used as a line-continuation character. Remove the underscore from the end of the line when you create this query.
   Query Name: FormatZIPCodes
   Query Type: Select Query
   
   Field: Postal Code: IIf([PCode] Like "#####-", Left([PCode], _
        Len([PCode])-1), IIf([PCode] Like _
        "#########",Format([PCode], "@@@@@-@@@@"), _
        [PCode]))
3. Run the query. Note that trailing hyphens are not displayed and that a hyphen appears after the fifth digit in nine-digit ZIP codes. You can use this query instead of your table when you create your report or share the data with another application. This select query displays formatted ZIP codes but it does not alter your table's existing ZIP code data.

For more information about update queries, click Microsoft Access Help on the Help menu, type create a query in the Office Assistant or the Answer Wizard, and then click Search to view the topic.

For more information about input masks, click Microsoft Access Help on the Help menu, type create an input mask to control how data in entered in a field or control in the Office Assistant or the Answer Wizard, and then click Search to view the topic.

For more information about using Microsoft Access data in Microsoft Word, click Microsoft Access Help on the Help menu, type export a table or query to a Microsoft word mail merge data source file in the Office Assistant or the Answer Wizard, and then click Search to view the topic.