Sub InsertPathFileSheetFormula()
    Select Case Left(ActiveCell.Formula, 4)
        Case ""
            ActiveCell.FormulaR1C1 = "=CELL(""filename"",R1C1)"
        Case "=CEL"
            ActiveCell.FormulaR1C1 = "=MID(CELL(""filename"",R1C1),FIND(""["",CELL(""filename"",R1C1))+1," & Chr(10) & "FIND(""]"",CELL(""filename"",R1C1))-FIND(""["",CELL(""filename"",R1C1))-1)"
        Case "=MID"
            ActiveCell.FormulaR1C1 = "=LEFT(CELL(""filename"",R1C1),FIND(""["",CELL(""filename"",R1C1),1)-1)"
        Case "=LEF"
            ActiveCell.FormulaR1C1 = "=RIGHT(CELL(""filename"",R1C1),LEN(CELL(""filename"",R1C1))- FIND(""]"",CELL(""filename"",R1C1),1))"
        Case "=RIG"
            ActiveCell.FormulaR1C1 = ""
    End Select
End Sub