VBA adding time in milliseconds

G

Gum

I have this:
Now() is current time.

Function myTime()
Dim t As Variant
t = Now() + TimeValue("00:00:20")
myTime= Format(t, "hh:mm:ss") & "." & Right(Format(Timer, "#0.00"), 2)
End Function

This adds 20 seconds to now()

I require to add milliseconds to Now() rather than seconds to get mytime().
How can this be done?
 
P

Peter T

One second as a fraction of a day is
1/(24-60*60)
so for milliseconds divide by another 1000

Be aware though that accuracy to that degree will not be stored in a 'Date'
variable, also the Now function only returns the time to an accuracy one
second.

Depending on what you are doing, eg looking for some sort of timer, there
are different approaches.

Regards,
Peter T
 
G

Gum

A type of timer where the instance of an event is captured, say t and after t
+ Delta t, where deta t is a in milliseconds, an event is triggered. So I
will use a comparator:
if time t plus delta t > time t Then
triggerevent
....
if now() is an approximation to the nearest second, I can see the problem
with my formulation. I am also looking for a solution with the minimum
footprint.
 
P

Peter T

Not sure I quite understand how you intend to implement but here are a
couple of ideas for a timer

Public Declare Function GetTickCount Lib "kernel32.dll" () As Long

Sub test()
Dim t As Single
Dim m As Long

t = Timer ' seconds
m = GetTickCount ' milliseconds

Range("A1:B1") = 123
For i = 1 To 40000
x = Range("a1") + Range("b1")
Next

t = Timer - t
m = GetTickCount - m

Debug.Print t, m

End Sub


The Gettickcount API returns milliseconds since the computer was turned on,
allowing for the overhead of calling the function consider it is accurate to
say better than 1/100th sec', considerably more accurate than Timer
function.

The Timer function returns seconds since midnight and updates about 18 times
/ second. That's enough for many purposes but note it resets at midnight.

There are other more accurate API methods but one of the above should be
sufficient for most purposes.

Regards,
Peter T
 
G

Gum

I used Timer previously and was thinking of writing a routine to adjust for
that Midnight reset, so the GetTickCount will address that problem too. Your
explanation of the code is quite invaluable.
 

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