Fastest way to separate the digits of an int into an array in .NET?

Question

I want to separate the digits of an integer, say 12345, into an array of bytes {1,2,3,4,5}, but I want the most performance effective way to do that, because my program does tha

Answer 1

I haven't benchmarked this or anything, but I think this would be the simplest answer. Correct me if I'm wrong.

    Dim num As Integer = 147483647
    Dim nDigits As Integer = 1 + Convert.ToInt32(Math.Floor(Math.Log10(num)))
    Dim result(nDigits - 1) As Integer

    For a As Integer = 1 To nDigits
        result(a - 1) = Int(num / (10 ^ (nDigits - a))) Mod 10
    Next

** EDIT **

Revised the function because exponents seem to be very expensive.

Private Function Calc(ByVal num As Integer) As Integer()
    Dim nDigits As Int64 = 1 + Convert.ToInt64(Math.Floor(Math.Log10(num)))
    Dim result(nDigits - 1) As Integer
    Dim place As Integer = 1

    For a As Integer = 1 To nDigits
        result(nDigits - a) = Int(num / place) Mod 10
        place = place * 10
    Next

    Return result
End Function

This benchmarks to around 775k/sec (for numbers 9 digits or less). Drop the maximum digits to 7 and it benches at 885k/s. 5 digits at 1.1m/s.