XL97: Cells That Contain User-Defined Functions Not Recalculated, Return #Value (244466)

CAUSE

This problem occurs when the following conditions are true:

The recalculation is invoked by means of the Calculate method.
-and-
An untrapped run-time error occurs in a user-defined function (UDF) while recalculating a cell.

When the run-time error occurs, Excel stops the recalculation for the worksheet. All cells that have not been updated and are referencing the UDF returns #Value.

However, when you update the sheet by pressing the F9, only the cells in which the run-time error occurred returns #Value.

WORKAROUND

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To work around this problem, press CTRL+ALT+F9 to force the values to be recalculated. When you do this, any formulas that refer to user-defined functions are recalculated correctly.

To prevent this problem from occurring, add error-handling code to your user-defined function, for example:

   Function MyFunction(CellRange As Object) As String
       On Error GoTo ErrorHandler                       'new line
       If CellRange.Interior.Pattern = xlNone Then
           MyFunction = "yes"
       Else
           MyFunction = "no"
       End If
       Exit Function                                    'new line
   ErrorHandler:                                        'new line
       '  You may want to use the following statement 
       '  to output the type of error result instead
       '  of a string result.
       'MyFunction = CVErr(xlErrValue) 
       MyFunction = "error"                             'new line
   End Function

In this user-defined function, the line "On Error GoTo ErrorHandler" causes the function to continue if an error occurs. In this case, the error- handling code causes the function to return a value of "error," instead of "yes" or "no." After the formulas return "error," press CTRL+ALT+F9 to recalculate the worksheet.

MORE INFORMATION

In Microsoft Excel 97, if a user-defined function returns an error value, the formula that called the user-defined function and any other formulas that call the same user-defined function may fail to be recalculated properly. When this occurs, the formulas may return a #VALUE! error.

Also, if the user-defined function returns an error value, any running Visual Basic subroutine that caused the recalculation to occur may stop. This may cause problems if the subroutine is running unattended.

To see examples of these problems, follow these steps:

In Microsoft Excel 97, create a new workbook.
On the Tools menu, and point to Macro.
Click Visual Basic Editor, and then, on the Insert menu, click Module.

Type the following code into the new module:

      Function MyFunction(CellRange As Object) As String

          'This line will fail when you delete a row from the worksheet.
          If CellRange.Interior.Pattern = xlNone Then
              MyFunction = "yes"
          Else
              MyFunction = "no"
          End If
      End Function

      Sub TestDelete()
          Rows(2).Delete              'Deleting a row forces
                                      'recalculation.
          MsgBox "Delete succeeded."
      End Sub

On the File menu, click Close and Return to Microsoft Excel.
Select cells A10:A12 in the worksheet, and then type the following formula, and then press CTRL+ENTER:
```
=MyFunction(C10)
						
```
All three cells (A10, A11, A12) display the value "yes."
On the Tools menu, point to Macro, and then click Macros. Select TestDelete, and then click Run.

Note that the three cells (A9, A10, A11) display the #VALUE! error value. Note also that the message box in the TestDelete subroutine is not displayed.
Press CTRL+ALT+F9.

The three formulas are recalculated correctly.

If you use the MyFunction function in the "Workaround" section, the formulas do not return a #VALUE! error value when you run the TestDelete subroutine, and the message box in TestDelete is displayed correctly. However, you still must press CTRL+ALT+F9 to force the formulas to display the correct value, which is "yes."

XL97: Cells That Contain User-Defined Functions Not Recalculated, Return #Value (244466)

SYMPTOMS

CAUSE

RESOLUTION

WORKAROUND

STATUS

MORE INFORMATION