如何在 Excel 中为不同的用户设置密码以保护各个工作表？

Option Explicit
Dim gUserName As String
Dim gUserPass As String
Private Sub Workbook_Open()
'Updateby ExtendOffice
Dim xWShs As Sheets
Dim xWSh As Worksheet
Dim xUserName As String
Dim xPass As String
Dim xBolH As Boolean
GTINPUT:
xUserName = InputBox("Enter the user name")
If TypeName(xUserName) = "String" Then
    If xUserName = "" Then
        Exit Sub
    End If
End If
xUserName = LCase(xUserName)
xPass = InputBox("User name:" & xUserName & Chr(13) & Chr(10) & "Enter the password:")
If TypeName(xPass) = "String" Then
    If xPass = "" Then
    MsgBox "The password is incorrect, please enter the user name and password again."
    GoTo GTINPUT
    End If
Else
    MsgBox "The password is incorrect, please enter the user name and password again."
    GoTo GTINPUT
End If
Set xWShs = Worksheets
xBolH = False
For Each xWSh In Worksheets
    If xWSh.Name = xUserName Then
    xBolH = True
    Exit For
    End If
Next
If xBolH Then
Set xWSh = xWShs(xUserName)
On Error GoTo GTINPUT2
xWSh.Unprotect (xPass)
xWSh.Visible = True
xWSh.Activate
Else
Set xWSh = xWShs.Add
xWSh.Name = xUserName
xWSh.Activate
End If
gUserName = xUserName
gUserPass = xPass
Exit Sub
GTINPUT2:
    MsgBox "The password is incorrect, please enter the user name and password again."
    GoTo GTINPUT
End Sub
Private Sub Workbook_BeforeClose(Cancel As Boolean)
Dim xWSh As Worksheet
On Error Resume Next
Set xWSh = Worksheets(gUserName)
xWSh.Protect Password:=gUserPass, DrawingObjects:=False, Contents:=True, Scenarios:= _
False, AllowFormattingCells:=True, AllowFormattingColumns:=True, _
AllowFormattingRows:=True, AllowInsertingColumns:=True, AllowInsertingRows _
:=True, AllowInsertingHyperlinks:=True, AllowDeletingColumns:=True, _
AllowDeletingRows:=True, AllowSorting:=True, AllowFiltering:=True, _
AllowUsingPivotTables:=True
For Each xWSh In Worksheets
    If xWSh.Name <> "Main" Then
        xWSh.Visible = xlSheetVeryHidden
    End If
Next xWSh
ActiveWorkbook.Save
End Sub