VB.Net/Development/Date Operation
Содержание
Add a day, a month and a year to a Date
<source lang="vbnet"> Imports System Public Class MainClass
Shared Sub Main() Dim dteStartDate As Date Dim dteChangedDate As Date "Start off in 2400 dteStartDate = #2/28/2400# "Add a day and display the results dteChangedDate = dteStartDate.AddDays(1) System.Console.WriteLine(dteChangedDate.ToLongDateString) "Add some months and display the results dteChangedDate = dteStartDate.AddMonths(6) System.Console.WriteLine(dteChangedDate.ToLongDateString) "Subtract a year and display the results dteChangedDate = dteStartDate.AddYears(-1) System.Console.WriteLine(dteChangedDate.ToLongDateString) End Sub
End Class
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Add time (days, hours) to current time
<source lang="vbnet"> Imports System.IO Module Module1
Sub Main() Dim Dt As DateTime = Now() Dim NewDT As DateTime = Now() Console.WriteLine("Current date and time: " & Dt) NewDT = NewDT.AddHours(5) Console.WriteLine("Five hours from now is: " & NewDT) End Sub
End Module
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Date Time and TimeSpan Demo
<source lang="vbnet"> Imports System Imports System.Diagnostics Public Class MainClass
Shared Sub Main() Const TRIALS As Integer = 10000000 Dim start_time As DateTime Dim stop_time As DateTime Dim elapsed_time As TimeSpan Dim i As Integer start_time = Now For i = 1 To TRIALS Next i stop_time = Now elapsed_time = stop_time.Subtract(start_time) Console.WriteLine(elapsed_time.TotalSeconds.ToString("0.000000")) start_time = Now For i = 1 To TRIALS Next i stop_time = Now elapsed_time = stop_time.Subtract(start_time) Console.WriteLine(elapsed_time.TotalSeconds.ToString("0.000000")) End Sub
End Class
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Date Time Subtraction
<source lang="vbnet"> Imports System Public Class MainClass
Shared Sub Main(ByVal args As String()) Dim date1 As Date = #7/20/2004# Dim date2 As Date = #8/7/2004# Dim elapsed_time As TimeSpan elapsed_time = Date.op_Subtraction(date2, date1) Console.WriteLine(elapsed_time.Days.ToString) End Sub
End Class
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Multiply Time Span
<source lang="vbnet"> Imports System Public Class MainClass
Shared Sub Main(ByVal args As String()) Dim ts1, ts2 As TimeSpan ts1 = New TimeSpan(1, 2, 3) ts2 = New TimeSpan(ts1.Ticks * 12) Console.WriteLine(ts1.ToString) Console.WriteLine(ts2.ToString) End Sub
End Class
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