Handle cancellation of InputBox to select range

Question 1

This is a problem when selection a range with an inputbox. Excel returns an error before the range is returned, and it carries this error on when you press cancel.

You should therefore actively handle this error. If you don't want anything to happen when you press cancel, you can just use the code like this:

Sub SetRange()
    Dim selectRange As Range

    On Error Resume Next
        Set selectRange = Application.InputBox("Select your range", "Hello", , , , , , 8)
    Err.Clear
    On Error GoTo 0
End Sub

Question 2

While this question is a bit older I still want to show the proper way to do it without errors. You can do it either to it via function or with a sub.

Your main procedure is something like this:

Sub test()
  Dim MyRange As Range

  testSub Application.InputBox("dada", , , , , , , 8), MyRange 'doing via Sub
  Set MyRange = testFunc(Application.InputBox("dada", , , , , , , 8)) ' doing via function

  If MyRange Is Nothing Then
    Debug.Print "The InputBox has been canceled."
  Else
    Debug.Print "The range " & MyRange.Address & " was selected."
  End If
End Sub

the Sub-way (funny) would be:

Sub testSub(ByVal a As Variant, ByRef b As Range)
  If TypeOf a Is Range Then Set b = a
End Sub

And the function would look like:

Function testFunc(ByVal a As Variant) As Range
  If TypeOf a Is Range Then Set testFunc = a
End Function

Now simply use the way you like and delete the unused line.

If calling a sub or a function you do not need to Set the parameter. That said, it doesn't matter if the InputBox returns an object or not. All you need to do, is to check if the parameter is the object you want or not and then act accordingly to it.

EDIT

Another smart way is using the same behavior with a collection like this:

Sub test()
  Dim MyRange As Range
  Dim MyCol As New Collection

  MyCol.Add Application.InputBox("dada", , , , , , , 8)
  If TypeOf MyCol(1) Is Range Then Set MyRange = MyCol(1)
  Set MyCol = New Collection

  If MyRange Is Nothing Then
    Debug.Print "The inputbox has been canceled"
  Else
    Debug.Print "the range " & MyRange.Address & " was selected"
  End If
End Sub

If you still have any questions, just ask ;)

Question 3

I'm late to the party here but this was the only place I could find that explained why I was having trouble just checking my variable for nothing. As explained in the accepted answer, the vbCancel on a range object isn't handled the same way as a string object. The error must be caught with an error handler.

I hate error handlers. So I segregated it to its own function

Private Function GetUserInputRange() As Range
    'This is segregated because of how excel handles cancelling a range input
    Dim userAnswer As Range
    On Error GoTo inputerror
    Set userAnswer = Application.InputBox("Please select a single column to parse", "Column Parser", Type:=8)
    Set GetUserInputRange = userAnswer
    Exit Function
inputerror:
    Set GetUserInputRange = Nothing
End Function

Now in my main sub I can

dim someRange as range
set someRange = GetUserInputRange
if someRange is Nothing Then Exit Sub

Anyhow this is not the same as the accepted answer because it allows the user to only handle this error with a specific error handler and not need to resume next or have the rest of the procedure handled the same way. In case anyone ends up here like I did.

Question 4

I have found that checking for the "Object required" error that you mentioned is one way of handling a cancel.

On Error Resume Next
dim selectRange as Range
' InputBox will prevent invalid ranges from being submitted when set to Type:=8.
Set selectRange = Application.InputBox("Select your range", "Hello", , , , , , 8)
' Check for cancel: "Object required".
If Err.Number = 424 Then
    ' Cancel.
    Exit Sub
End If
On Error GoTo 0

Question 5

I went with a cleaner solution:

Dim InputValue As Range
On Error Resume Next
Set InputValue = Application.InputBox("Select Range","Obtain Range", Type:=8)
Err.Clear
If InputValue Is Nothing Then
    GoTo ExitApp:
End If

This will clear the error message and catch the "nothing" value returned to InputValue. Usefully, this doesn't interrupt a submission of no information, which Excel just loops back to requesting input automatically, but the user may need to add additional error handling for bad data entry.

Down code, add:

ExitApp:
    Exit Sub

For exiting, which can be usefully shared between multiple input cancel handlers.

Question 6

If I use Dirks second answer inside a for loop and I want to exit my sub, it is not enough to execute an Exit Sub inside his IF statement
I found that if I use Exit Sub standalone inside a for loop, I will not exit my sub in all cases, however, in most cases only exit the for loop.

Here you have Dirks code

EDIT

Another smart way is using the same behavior with a collection like this:

 Sub test()
  Dim MyRange As Range
  Dim MyCol As New Collection

  MyCol.Add Application.InputBox("dada", , , , , , , 8)
  If TypeOf MyCol(1) Is Range Then Set MyRange = MyCol(1)
  Set MyCol = New Collection

  If MyRange Is Nothing Then
    Debug.Print "The input box has been canceled"
  Else
    Debug.Print "the range " & MyRange.Address & " was selected"
  End If
 End Sub

If you still have any questions, just ask ;)

Here is what I made to work as a example:

Sub test()
  Dim i as Integer
  Dim boolExit as Boolean
  Dim MyRange As Range
  Dim MyCol As New Collection
  boolExit = False

  For i = 1 To 5 Then
    MyCol.Add Application.InputBox("dada", , , , , , , 8)
    If TypeOf MyCol(1) Is Range Then Set MyRange = MyCol(1)
    Set MyCol = New Collection

    If MyRange Is Nothing Then
      Debug.Print "The inputbox has been canceled"
      boolExit = True
      Exit Sub
    Else
      Debug.Print "the range " & MyRange.Address & " was selected"
    End If
  Next i

  If boolExit = True Then Exit Sub 'Checks if Sub should be exited

  Debug.Print "Program completed"      
End Sub

If you press cancel at anytime in the five runs, the Sub is shutdown with the above code and you will never see Program completed printed.

However if you remove boolExit from the above, the code after the For loop is still being run if you press cancel in any of the 1+ runs and you will see Program completed even when that is not true.