Question

请帮忙！我需要得到总时数和分钟数，格式为＆＃34; HH：mm＆＃34;来自ListBox，例如：

    11:20
    22:40
    34:00

总计：68：00

我尝试使用Datetime和TimeSpan，但它有错误：

＆＃34;日历中不支持字符串表示的DateTime System.Globalization.GregorianCalendar＆＃34;

这是我的代码：

    ListBox_monthtime.Items.Add("11:20")
    ListBox_monthtime.Items.Add("22:40")
    ListBox_monthtime.Items.Add("34:00")

    'SUM TIMES IN LISTBOX
    Dim MyDateTimeMonthly As DateTime
    Dim MyTimeSpanMonthly As New TimeSpan

    For Each S As String In ListBox_monthtime.Items
        MyDateTimeMonthly = DateTime.ParseExact(S, "HH:mm", System.Globalization.CultureInfo.InvariantCulture)
        MyTimeSpanMonthly = MyTimeSpanMonthly.Add(New TimeSpan(MyDateTimeMonthly.Day, MyDateTimeMonthly.Hour, MyDateTimeMonthly.Minute, 0))
    Next

    monthtime_txt.Text = (MyTimeSpanMonthly.Days * 24 + MyTimeSpanMonthly.Hours) & ":" & MyTimeSpanMonthly.Minutes

Answer 1

也许这会有所帮助：

ListBox_monthtime.Items.Add("11:43")
ListBox_monthtime.Items.Add("22:56")
ListBox_monthtime.Items.Add("34:21")

Dim totalHours As Integer
Dim totalMinutes As Integer
For Each S As String In ListBox_monthtime.Items
    totalHours += S.Split(":")(0)
    totalMinutes += S.Split(":")(1)
Next

Dim remainder = totalMinutes Mod 60
totalHours += totalMinutes / 60

Dim totalTime = totalHours & ":" & remainder.ToString("D2")
monthtime_txt.Text = totalTime

你仍然会施放Strings-Integers，所以我会把它放在Try / Catch中

Answer 2

您不能使用小于24的小时值从字符串创建DateTime或Timespan。您需要自己解析输入并将其转换为TimeSpan.parse()使用的有效字符串。< / p>

Dim TotalTime As TimeSpan = TimeSpan.Zero
For Each item As String In ListBox_monthtime.Items
    TotalTime = TotalTime.Add(TimeSpan.Parse(FormatTimeString(item)))
Next
Me.monthtime_txt.Text = $"{CInt(TotalTime.TotalHours).ToString}:{TotalTime.Minutes}"


Private Function FormatTimeString(TimeString As String) As String
    Dim timeArr() As String = TimeString.Split(":")
    If CInt(timeArr(0)) > 24I Then
        Dim d As Int32 = CInt(timeArr(0)) \ 24I
        FormatTimeString = $"{d}:{(CInt(timeArr(0)) - (24I * d)).ToString}:{timeArr(1)}:00"
    Else
        FormatTimeString = TimeString
    End If
End Function

VB.NET如何在Listbox中获得总小时数和分钟数

2 个答案: