任务
我正在做一些性能测试，测量开始时间（st1）和结束时间（st1）之间的经过时间。
正如我还想显示毫秒，我正在使用API函数GetSystemTime：
GetSystemTime st1 ' get start time as system time
GetSystemTime st2 ' get end time as system time
问题
不可能简单地减去
st2 - st1
，因为这会导致错误13消息。到目前为止，我没有找到任何解决方案，但是成功地围绕函数SystemTimeDiff（st1作为SYSTEMTIME，st2作为SYSTEMTIME）创建了一个简单的工作。
题
我想知道是否存在更简单的方法或SystemTimeDiff函数-例如与DateDiff相当？
码
Option Explicit
' API Declaration
Private Declare Sub GetSystemTime Lib "kernel32" ( _
lpSystemTime As SYSTEMTIME)
Private Type SYSTEMTIME
wYear As Integer
wMonth As Integer
wDayOfWeek As Integer
wDay As Integer
wHour As Integer
wMinute As Integer
wSecond As Integer
wMilliseconds As Integer
End Type
' ================
' Performance Test
' ================
Sub TestSystemTimeDifference()
Dim st1 As SYSTEMTIME
Dim st2 As SYSTEMTIME
GetSystemTime st1 ' Start time
' Do something
' ............
GetSystemTime st2 ' End time
' ================
' Show System time elapsed with milliseconds as work around
' ================
MsgBox SystemTimeDiff(st1, st2), vbInformation, "Systemtime elapsed"
End Sub
' ==============
' My Work around
' ==============
Function SystemTimeDiff(st1 As SYSTEMTIME, st2 As SYSTEMTIME)
Dim msec1 As Integer: Dim msec2 As Integer
Dim timetaken As Date
msec1 = Val(Left(Split(FormatSystemTime(st1) & ".", ".")(1) & "000", 3))
msec2 = Val(Left(Split(FormatSystemTime(st2) & ".", ".")(1) & "000", 3))
If msec2 < msec1 Then msec2 = msec2 + 1000
timetaken = CDate(Split(FormatSystemTime(st2) & ".", ".")(0)) - CDate(Split(FormatSystemTime(st1), ".")(0))
SystemTimeDiff = FormatSystemTime(st1) & vbNewLine & FormatSystemTime(st2) & vbNewLine & _
(Format(Hour(timetaken), "00") & ":" & Format(Minute(timetaken), "00") & ":" & Format(Second(timetaken), "00")) & _
"." & Format(msec2 - msec1, "000")
End Function
Function FormatSystemTime(st As SYSTEMTIME) As String
' Purpose: returns formatted system time with milliseconds
' cf Site: http://www.vbarchiv.net/tipps/tipp_1493-timestamp-inkl-millisekunden.html
With st
FormatSystemTime = Format(.wHour, "00") & ":" & Format(.wMinute, "00") & ":" & _
Format(.wSecond, "00") & "." & Format(.wMilliseconds, "000")
End With
End Function
最佳答案
这个怎么样
Private Declare Function GetTickCount Lib "kernel32" () As Long
Sub timeMe()
Dim start As Long, fini As Long
Dim total As Long
Dim ms As Long, sec As Long, min As Long, hr As Integer
start = GetTickCount()
Dim i, j: For i = 0 To 1000000: j = i ^ 2: Next i
fini = GetTickCount()
total = fini - start
' total = 7545023 ' test value: 2:05:45.023
' total = 460382417 ' test value: 127:53:02.417
ms = total Mod 1000
sec = total \ 1000
min = sec \ 60
hr = min \ 60
sec = sec Mod 60
min = min Mod 60
Debug.Print "runtime "; hr & ":" & Format(min, "00") & ":" & Format(sec, "00") & "." & Format(ms, "000")
End Sub