One Line or Two Lines?

[Pradeep1210]

Just like the popular view, I thought lesser code means better performance.

I tested:

value = CType(object, ObjectType).Property

against

Dim obj As ObjectType = CType(object, ObjectType)
value = obj.Property

The first method doesn't need an intermediate variable in between to store my object. This should also put less burden on the garbage collector as there is no variable. The 2nd way has an intermediate variable required in memory. So I thought it must be faster using the first way rather than the second way. But test results shows just the opposite here.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Dim sw As New Stopwatch, senderName As String
 
    For i As Integer = 1 To 5
        sw.Reset() : sw.Start()
        For j As Integer = 1 To 100000000
            senderName = CType(sender, Button).Name
        Next
        sw.Stop()
        Debug.Print("One Line : " & sw.ElapsedMilliseconds)
 
        sw.Reset() : sw.Start()
        For j As Integer = 1 To 100000000
            Dim btn As Button = CType(sender, Button)
            senderName = btn.Name
        Next
        sw.Stop()
        Debug.Print("Two Lines: " & sw.ElapsedMilliseconds)
    Next
End Sub

This is the result:

One Line : 3786
Two Lines: 3677
One Line : 3787
Two Lines: 3683
One Line : 3787
Two Lines: 3677
One Line : 3790
Two Lines: 3678
One Line : 3783
Two Lines: 3677

Anyone know why this happens? Is the CLR doing some smart optimizations?

Pradeep