DateTime.AddSeconds(Double) 方法

定義

傳回新的 DateTime,將這個執行個體的值加上指定的秒數。

public:
 DateTime AddSeconds(double value);
public DateTime AddSeconds (double value);
member this.AddSeconds : double -> DateTime
Public Function AddSeconds (value As Double) As DateTime

參數

value
Double

整數和小數的秒數。 value 參數可以是負數或正數。

傳回

物件,其值為這個執行個體所表示日期和時間加上 value 所表示秒數的總和。

例外狀況

範例

下列範例會使用 方法, AddSeconds 將 30 秒和一天內的秒數新增至 DateTime 值。 然後會顯示每個新值,並顯示其與原始值之間的差異。 差異會顯示為時間範圍和一些刻度。

using System;

public class Example
{
   public static void Main()
   {
      string dateFormat = "MM/dd/yyyy hh:mm:ss";
      DateTime date1 = new DateTime(2014, 9, 8, 16, 0, 0);
      Console.WriteLine("Original date: {0} ({1:N0} ticks)\n",
                        date1.ToString(dateFormat), date1.Ticks);

      DateTime date2 = date1.AddSeconds(30);
      Console.WriteLine("Second date:   {0} ({1:N0} ticks)",
                        date2.ToString(dateFormat), date2.Ticks);
      Console.WriteLine("Difference between dates: {0} ({1:N0} ticks)\n",
                        date2 - date1, date2.Ticks - date1.Ticks);

      // Add 1 day's worth of seconds (60 secs. * 60 mins * 24 hrs.
      DateTime date3 = date1.AddSeconds(60 * 60 * 24);
      Console.WriteLine("Third date:    {0} ({1:N0} ticks)",
                        date3.ToString(dateFormat), date3.Ticks);
      Console.WriteLine("Difference between dates: {0} ({1:N0} ticks)",
                        date3 - date1, date3.Ticks - date1.Ticks);
   }
}
// The example displays the following output:
//    Original date: 09/08/2014 04:00:00 (635,457,888,000,000,000 ticks)
//
//    Second date:   09/08/2014 04:00:30 (635,457,888,300,000,000 ticks)
//    Difference between dates: 00:00:30 (300,000,000 ticks)
//
//    Third date:    09/09/2014 04:00:00 (635,458,752,000,000,000 ticks)
//    Difference between dates: 1.00:00:00 (864,000,000,000 ticks)
open System

let dateFormat = "MM/dd/yyyy hh:mm:ss"
let date1 = DateTime(2014, 9, 8, 16, 0, 0)
printfn $"Original date: {date1.ToString dateFormat} ({date1.Ticks:N0} ticks)\n"

let date2 = date1.AddSeconds 30
printfn $"Second date:   {date2.ToString dateFormat} ({date2.Ticks:N0} ticks)"
printfn $"Difference between dates: {date2 - date1} ({date2.Ticks - date1.Ticks:N0} ticks)\n"

// Add 1 day's worth of seconds (60 secs. * 60 mins * 24 hrs.
let date3 = date1.AddSeconds(60. * 60. * 24.)
printfn $"Third date:    {date3.ToString dateFormat} ({date3.Ticks:N0} ticks)" 
printfn $"Difference between dates: {date3 - date1} ({date3.Ticks - date1.Ticks:N0} ticks)"

// The example displays the following output:
//    Original date: 09/08/2014 04:00:00 (635,457,888,000,000,000 ticks)
//
//    Second date:   09/08/2014 04:00:30 (635,457,888,300,000,000 ticks)
//    Difference between dates: 00:00:30 (300,000,000 ticks)
//
//    Third date:    09/09/2014 04:00:00 (635,458,752,000,000,000 ticks)
//    Difference between dates: 1.00:00:00 (864,000,000,000 ticks)
Module Example
   Public Sub Main()
      Dim dateFormat As String = "MM/dd/yyyy hh:mm:ss"
      Dim date1 As Date = #09/08/2014 16:00#
      Console.WriteLine("Original date: {0} ({1:N0} ticks)", _
                        date1.ToString(dateFormat), date1.Ticks)
      Console.WriteLine()
      
      Dim date2 As Date = date1.AddSeconds(30)
      Console.WriteLine("Second date:   {0} ({1:N0} ticks)", _
                        date2.ToString(dateFormat), date2.Ticks)
      Console.WriteLine("Difference between dates: {0} ({1:N0} ticks)", _
                        date2 - date1, date2.Ticks - date1.Ticks)                        
      Console.WriteLine()
      
      ' Add 1 day's worth of seconds (60 secs. * 60 mins * 24 hrs.
      Dim date3 As Date = date1.AddSeconds(60 * 60 * 24)
      Console.WriteLine("Third date:    {0} ({1:N0} ticks)", _
                        date3.ToString(dateFormat), date3.Ticks)
      Console.WriteLine("Difference between dates: {0} ({1:N0} ticks)", _
                        date3 - date1, date3.Ticks - date1.Ticks)                        
   End Sub
End Module
' The example displays the following output:
'    Original date: 09/08/2014 04:00:00 (635,457,888,000,000,000 ticks)
'
'    Second date:   09/08/2014 04:00:30 (635,457,888,300,000,000 ticks)
'    Difference between dates: 00:00:30 (300,000,000 ticks)
'
'    Third date:    09/09/2014 04:00:00 (635,458,752,000,000,000 ticks)
'    Difference between dates: 1.00:00:00 (864,000,000,000 ticks)

備註

這個方法不會變更這個 DateTime 的值。 相反地,它會傳回新的 DateTime ,其值為此作業的結果。

的分數部分 value 是第二個的小數部分。 例如,4.5 相當於 4 秒、500 毫秒和 0 個刻度。

在 .NET 6 和舊版中 value ,參數會四捨五入至最接近的毫秒。 在 .NET 7 和更新版本中,會使用 參數的完整 Doublevalue 精確度。 不過,由於浮點數數學的固有不精確性,因此產生的精確度會有所不同。

適用於

另請參閱