Visual Basic Macro to List Circular References

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Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers 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 requirements. Precedents are the cells referenced, directly or indirectly, by a formula. A circular reference occurs whenever the cell containing the circular reference formula is included in the formula's precedents.

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
				

To use this macro, run the FindCircRefs macro from the Microsoft Excel worksheet for which you want to find circular references. A new sheet will be added to the active workbook, listing the cell addresses of circular references in column A, and the formula at that address in column B. If no circular references are found, the new sheet will be empty.