Convert.ToInt64 (Single) converts single-precision floating-point number to 64-bit signed integer.
Module Example Public Sub Main() Dim values() As Single = { Single.MinValue, -1.38e10, 0, 9.111e-16, 111.111, 2010.191, Single.MaxValue } Dim result As Long For Each value As Single In values Try result = Convert.ToInt64(value) Console.WriteLine(result) Catch e As OverflowException Console.WriteLine("{0} is outside the range of the Int64 type.", value) End Try Next End Sub End Module