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For…Each vs. For...Next

Using For...Next in arrays is a lot faster than For...Each. I'm not sure why this is caused, but probably also because you've got to use a variant as loop index for the "For...Each". And any serious programmer doesn't use a variant in his/her applications. I've used Lbound() and Ubound() in the For...Next loop, cause we do not have to worry about those two values, like in For...Each. No 500.000 iterations this time. I've done 1 iteration, the array was large enough to be precise enough. The test has been done 5 times though.

Used Code:

Code: Public Sub TestOne() Dim MyArray(1 To 100000) Dim I As Variant For Each I In MyArray Next End Sub Public Sub TestTwo() Dim MyArray(1 To 100000) Dim I As Long For I = LBound(MyArray) To UBound(MyArray) Next End Sub

For...Each % faster than For...Next	For...Each (sec)	For...Next (sec)
69,8%	0.070230	0.041363
39%	0.062214	0.044772
51,5%	0.062389	0.041175
30,9%	0.062814	0.047993
51,3%	0.061905	0.040924

User contributed notes:

Author: fish ()	Date: 17:09 04/09/2004
for collections, always use for each, it's many times faster
Author: SuperDre ()	Date: 10:06 23/06/2006
I agree with fish(), For Each isn't meant for using with simple arrays (it also only works with arrays of variants). And you made one other mistake, you only do a loop with nothing in it.. Try doing the same test but then assign something to the item.. I think you will get a completely different result then.. Because with every assignment, For..Next has to lookup the item every cycle, whereas For Each already has the Item..