VBA Inputbox Filter enhancements - vba

Question

the code below works fine. However, when a user doesn't include anything in the InputBox or clicks on the 'Close' button or inputs a value which doesn't exist I want it to display a msgbox stating the reason and delete sheets 'PreTotal'.
Is there a better way to handle user input? Need some help here on how to go about it. Thank you.
Sub Filterme()
Dim wSheetStart As Worksheet
Dim rFilterHeads As Range
Dim strCriteria As String
Set wSheetStart = ActiveSheet
Set rFilterHeads = Range("M1", Range("M1").End(xlToLeft))
With wSheetStart
.AutoFilterMode = False
rFilterHeads.AutoFilter
strCriteria = InputBox("Enter Date - MMDDYY")
If strCriteria = vbNullString Then Exit Sub
rFilterHeads.AutoFilter Field:=13, Criteria1:="=*" & strCriteria & "*"
End With
Worksheets("PreTotal").UsedRange.Copy
Sheets.Add.Name = "Total"
Worksheets("Total").Range("A1").PasteSpecial
End Sub

Answer 1

Is this what you are trying?
Change
If strCriteria = vbNullString Then Exit Sub
to
If strCriteria = vbNullString Then
MsgBox "You choose not to continue"
Application.DisplayAlerts = False
Worksheets("PreTotal").Delete
Application.DisplayAlerts = True
Exit Sub
End If
FOLLOWUP
Thanks #Rout - This worked. One more thing what if the input criteria does not exist in the sheet? How should I tackle that? – user823911 11 mins ago
Is this what you are trying? Also if you are filtering the range based on Col M (1st Col in the range) then change the line
rFilterHeads.AutoFilter Field:=13, Criteria1:="=*" & strCriteria & "*"
to
rFilterHeads.AutoFilter Field:=1, Criteria1:="=*" & strCriteria & "*"
CODE
Sub Filterme()
Dim wSheetStart As Worksheet
Dim rFilterHeads As Range, aCell As Range
Dim strCriteria As String
Set wSheetStart = ActiveSheet
Set rFilterHeads = Range("M1", Range("M1").End(xlToLeft))
With wSheetStart
.AutoFilterMode = False
strCriteria = InputBox("Enter Date - MMDDYY")
If strCriteria = vbNullString Then
MsgBox "You choose not to continue"
Application.DisplayAlerts = False
Worksheets("PreTotal").Delete
Application.DisplayAlerts = True
Exit Sub
End If
Set aCell = .Columns(13).Find(What:=strCriteria, LookIn:=xlValues, _
LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
MatchCase:=False, SearchFormat:=False)
If Not aCell Is Nothing Then
MsgBox "Search Criteria Not Found"
Exit Sub
End If
rFilterHeads.AutoFilter
rFilterHeads.AutoFilter Field:=13, Criteria1:="=*" & strCriteria & "*"
Sheets.Add.Name = "Total"
Worksheets("PreTotal").UsedRange.Copy
Worksheets("Total").Range("A1").PasteSpecial
End With
End Sub