Why does VBA ActiveWorkbook.SaveAs change the open spreadsheet?

My function is as follows:

Sub saveCSV()
    Application.DisplayAlerts = False
    ActiveWorkbook.SaveAs Filename:= _
    "c:\temp\file.csv", FileFormat:=xlCS开发者_高级运维V _
    , CreateBackup:=False
End Sub

I'm trying to export the active worksheet to CSV. When I run the code in the title, Book1.xlsm changes to file.csv and Sheet1 changes to file. The export works fine. How can I do the export without these unwanted side effects?

That's always how SaveAs has worked. The only way to get around this is to copy the worksheet and do a SaveAs on the copy, then close it.

EDIT: I should add an example as it's not that difficult to do. Here's a quick example that copies the ActiveSheet to a new workbook.

Dim wbk As Workbook
Set wbk = Workbooks.Add
ActiveSheet.Copy wbk.Sheets(1) ' Copy activesheet before the first sheet of wbk
wbk.SaveAs ....
wbk.Close

A complicated workbook may get issues with links and macros, but in ordinary scenarios this is safe.

EDIT 2: I'm aware of what you're trying to do, as your other question was about trying to trigger an export on every change to the sheet. This copy sheet approach presented here is likely to be highly disruptive.

My suggestion is to write a CSV file by hand to minimise GUI interruption. The sheet is likely to become unusable if the saves are occurring at high frequency. I wouldn't lay the blame for this at the door of Excel, it simply wasn't built for rapid saves done behind the scenes.

Here's a little routine that does what you want by operating on a copy of the original ... copy made via file scripting object. Hardcoded to operate on "ThisWorkbook" as opposed to active workbook & presumes ".xlsm" suffix - could tweak this to do the job I think:

Public Sub SaveCopyAsCsv()

Dim sThisFile As String: sThisFile = ThisWorkbook.FullName
Dim sCsvFile As String:  sTempFile = Replace(sThisFile, ".xlsm", "_TEMP.xlsm")

ThisWorkbook.Save ' save the current workbook

' copy the saved workbook ABC.xlsm to TEMP_ABC.xlsm
Dim fso As Object: Set fso = CreateObject("Scripting.FileSystemObject")
On Error Resume Next
Call fso.deletefile(sTempFile, True)  ' deletes prev temp file if it exists
On Error GoTo 0
Call fso.CopyFile(sThisFile, sTempFile, True)

' open the temp file & save as CSV
Dim wbTemp As Workbook
Set wbTemp = Workbooks.Open(sTempFile) ' open the temp file in excel
' your prev code to save as CSV
Application.DisplayAlerts = False
ActiveWorkbook.SaveAs FileName:="c:\temp\file.csv", FileFormat:=xlCSV,     CreateBackup:=False
wbTemp.Close ' close the temp file now that the copy has been made
Application.DisplayAlerts = True

' delete the temp file (if you want)
On Error Resume Next
Call fso.deletefile(sTempFile, True)  ' deletes the temp file
On Error GoTo 0

End Sub