XL: Visual Basic Macro to List Circular References

• Microsoft Excel for Windows, versions 5.0, 5.0c
• Microsoft Excel for the Macintosh, versions 5.0, 5.0a
• Microsoft Excel for Windows NT, version 5.0
• Microsoft Excel for Windows 95, versions 7.0, 7.0a
• Microsoft Excel 97 for Windows
• Microsoft Excel 98 Macintosh Edition

SUMMARY

In a Microsoft Excel worksheet, when a formula in a cell refers to the same cell it occupies, either directly or indirectly, a circular reference is created. In Microsoft Excel versions 5.0 and later, tracing tools are provided on the Auditing toolbar to help you locate unwanted circular references. Another way you can trace circular references is to create a Microsoft Visual Basic for Applications macro that produces a list of all cells containing circular references that occur in a single worksheet.

MORE INFORMATION

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The following sample Visual Basic macro generates a new sheet in a workbook and lists all circular references found on the active worksheet. The macro does this by testing each formula in the sheet to see if the cell containing the formula intersects the precedents of the formula.

NOTE: A limitation of this method is that the Precedents property in Visual Basic for Applications can only find precedents on the active sheet. The macro below will not find a circular reference that is caused by a remote reference.

Sample Visual Basic Procedure

On a module sheet, enter the following Visual Basic code:

   Sub FindCircRefs()
       ' Get source information.
       sourcesheet = ActiveSheet.Name
       Sheets.Add
       ' Get destination information.
       destsheet = ActiveSheet.Name
       destrange = ActiveCell.Address
       ' Return to source.
       Worksheets(sourcesheet).Activate
       rowcount = 0
       ' Trap for error in "result", indicating no circular reference.
       On Error GoTo notcircular

       ' Loop through every used cell in source.
       For Each Item In ActiveSheet.UsedRange
           ' Check to see if cell contains a formula.
           If Left(Item.Formula, 1) = "=" Then
               ' If cell intersects with precedents, cell has circular
               ' reference.
               result = Intersect(ActiveSheet.Range(Item.Address), _
                   ActiveSheet.Range(Item.Precedents.Address))

               Worksheets(destsheet).Range(destrange).Offset(rowcount, _
                   0).Value = Item.Address(False, False)

               Worksheets(destsheet).Range(destrange).Offset(rowcount, _
                   1).Value = "'" & Item.Formula

               rowcount = rowcount + 1
               ' Skip to here if not circular.
   skipitem:
           End If
       Next
       Exit Sub

   ' If error in "result", go here.
   notcircular:
       ' Skip cells that do not contain circular references.
       Resume skipitem
   End Sub