Restricting the user to delete the cell contents - excel

Question

Is there's any way to restrict the user from deleting the cell contents without using the protect method of excel. I have this code:
Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim ws As Worksheet
Set ws = ThisWorkbook.Worksheets("Sheet1")
If Not Intersect(Target, Range("C21:D" & ws.Range("C" & ws.Rows.Count).End(xlUp).Row)) Is Nothing Then
Cancel = True
MsgBox "You are not allowed to edit!", vbCritical + vbOKOnly
EndIf
End sub
But this only disallows the editing of the cell contents. I want make a function that would disallow the editing and deleting the data in a cell without using the protect method. Thanks!

Answer 1

Without lock and unlock, you can use this.
We have there one global variable to store selection value (to preserve beforechange state). Function SelectionChange, updating value of current cell, so we can restore cell value after users try.
Sub worksheet_change just controling, if user targeting specified row and column (can be adjusted for whole range), and if he try to change value, he is prompted and value is set back.
Dim prevValue As Variant
Private Sub worksheet_SelectionChange(ByVal target As Range)
prevValue = target.Value
End Sub
Private Sub worksheet_change(ByVal target As Range)
If target.Row = 5 And target.Column = 5 Then
If target.Value <> prevValue Then
target.Value = prevValue
MsgBox "You are not allowed to edit!", vbCritical + vbOKOnly
End If
End If
End Sub
edit: disable editing every cell which is not empty
Private Sub worksheet_change(ByVal target As Range)
If prevValue <> "" Then
If target.Value <> prevValue Then
target.Value = prevValue
MsgBox "You are not allowed to edit!", vbCritical + vbOKOnly
End If
End If
End Sub

Answer 2

Try my idea. Copy and paste these codes into the module of the sheet where the protected range is located. In my case it was called "Arkusz1". The protected range is "A1:A10".
Private Sub Worksheet_Change(ByVal Target As Range)
For Each cell In Range("A1:A10")
If cell.Text <> Sheets("hidden").Cells(cell.Row, cell.Column) Then
Call Undoing
End If
Next cell
End Sub
Private Sub Undoing()
Application.EnableEvents = False
Application.Undo
Application.EnableEvents = True
End Sub
In the "This_worksheet" module copy and paste this code:
Private Sub Workbook_Open()
Sheets.Add
ActiveSheet.Name = "hidden"
Sheets("Arkusz1").Range("A1:A10").Copy
Sheets("hidden").Select
ActiveSheet.Paste
Sheets("hidden").Select
ActiveWindow.SelectedSheets.Visible = False
End Sub
Private Sub Workbook_Close()
Sheets("hidden").Visible = True
Sheets("hidden").Delete
End Sub
You will have to change the name of the sheet from "Arkusz1" to "Sheet1" or any other name Your sheet has got.
The idea is as follows. Upon the opening of the workbook the application creates a hidden spreadsheet into which it copies the contents of protected cells. For some technical reasons I had to hide the sheet after the copy operation, otherwise it did not work on my computer. Then, any change of the sheet "Arkusz1" triggers the event which compares the contents of the protected range with the same range in the hidden sheet.
If there are any differences the application undoes the last action of the user.
Undoing has to be done when event handling by Excel is turned off, because undoing a previous action is also an event of changing the sheet and we would cause a cascade of events - every undo operation would trigger the event "worksheet_change" and it would never stop getting activated.
Application.EnableEvents = False
Application.Undo
Application.EnableEvents = True