Code That Allows User to Select Two Cells and Get the Difference as an Output

Be sure to put the start time first:

Function Span(Startime As Date, Stoptime As Date) As Date
Span = Stoptime - Startime: End Function

PHP Code: 

1:30:15    4:47:12    3:16:57 


PHP Code: 

1:30:15    4:47:12   =Span(H9,I9) 


XLAdept

Thank you for the expedient reply. What I'm really trying to do is build a macro that would subtract the min time from the max time of a User Selection that isn't a specified range until Selected and display the difference in any way but, the thing I can't figure out is how to get minimum and maximum values of a selection called up.
I fear I'm not doing a very good job of explaining myself.
The following is the idea of what I'm trying to accomplish but of course my syntax is all wrong and the code does not work. I'm really having trouble wrapping my head around VBA's hierarchy and syntax.

Sub MinMaxDiff()
    Dim StartTime As Date, StopTime As Date
    Dim Duration As Date
StartTime = Application.WorksheetFunction.Min(Range("Selection"))
StopTime = Application.WorksheetFunction.Max(Range("Selection"))
Duration = StopTime - StartTime

msgbox Duration

End Sub

Thank you to all of you who post to this forum. I have a piece of code that is working so far. If so inclined before I mark as solved could someone explain
why the following code works? I mostly don't understand why I sometimes need an object like range before selection and in this case omitting anything in front of Selection was the ticket. I got this working mostly by accident. Also is this the most efficient form of what I'm trying to accomplish?

Thanks

PHP Code: 

Sub MinMaxDiff()

Dim StartTime As Date, StopTime As Date
Dim Duration As Date, Rng As Range

    Set Rng = Selection
    StartTime = Application.WorksheetFunction.Min(Rng)
    StopTime = Application.WorksheetFunction.Max(Rng)
    Duration = StopTime - StartTime

    msgbox Duration

End Sub 


I am also unsure as to why I had to use the Set Rng = Selection.

You don't need to set the object if you use selection:

Sub MinMaxDiff(): Dim StartTime As Date, StopTime As Date, Duration As Date
    StartTime = Application.WorksheetFunction.MIN(Selection)
    StopTime = Application.WorksheetFunction.MAX(Selection)
    Duration = StopTime - StartTime

    MsgBox Duration   'Range("A19")=Duration

End Sub

But wouldn't you rather write the duration on the spreadsheet?

Here's a function and a sub to call it:

Function Duration(R As Range) As Date
Dim Startime As Date, Stoptime As Date
Startime = Application.WorksheetFunction.MIN(R)
Stoptime = Application.WorksheetFunction.MAX(R)
Duration = Stoptime - Startime: End Function

Sub PostElapsed()
Range("A19") = Duration(Selection)
End Sub

You're welcome! - Functions can also be used as formulas in the spreadsheet.

But you could reestablish the rng and, rather than actually selecting with the mouse, you could specify the actual range with the Set statement.