TimeSpan.FromHours Metodo

Definizione

Spazio dei nomi:

System

Assembly:

System.Runtime.dll

Overload

FromHours(Double)

Restituisce un TimeSpan che rappresenta un numero specificato di ore, in cui la specifica è accurata al millisecondo più vicino.

FromHours(Double)

Origine:

TimeSpan.cs

Restituisce un TimeSpan che rappresenta un numero specificato di ore, in cui la specifica è accurata al millisecondo più vicino.

public:
 static TimeSpan FromHours(double value);

public static TimeSpan FromHours (double value);

static member FromHours : double -> TimeSpan

Public Shared Function FromHours (value As Double) As TimeSpan

Parametri

value

Double

Numero di ore accurate per il millisecondo più vicino.

Restituisce

TimeSpan

Oggetto che rappresenta value.

Eccezioni

OverflowException

value è minore di TimeSpan.MinValue o maggiore di TimeSpan.MaxValue.

-o-

value è PositiveInfinity.

-o-

value è NegativeInfinity.

ArgumentException

value è uguale a NaN.

Esempio

Nell'esempio seguente vengono creati diversi oggetti TimeSpan utilizzando il metodo FromHours.

// Example of the TimeSpan::FromHours( double ) method.
using namespace System;
void GenTimeSpanFromHours( double hours )
{
   
   // Create a TimeSpan object and TimeSpan string from 
   // a number of hours.
   TimeSpan interval = TimeSpan::FromHours( hours );
   String^ timeInterval = interval.ToString();
   
   // Pad the end of the TimeSpan string with spaces if it 
   // does not contain milliseconds.
   int pIndex = timeInterval->IndexOf( ':' );
   pIndex = timeInterval->IndexOf( '.', pIndex );
   if ( pIndex < 0 )
      timeInterval = String::Concat( timeInterval, "        " );

   Console::WriteLine( "{0,21}{1,26}", hours, timeInterval );
}

int main()
{
   Console::WriteLine( "This example of TimeSpan::FromHours( double )\n"
   "generates the following output.\n" );
   Console::WriteLine( "{0,21}{1,18}", "FromHours", "TimeSpan" );
   Console::WriteLine( "{0,21}{1,18}", "---------", "--------" );
   GenTimeSpanFromHours( 0.0000002 );
   GenTimeSpanFromHours( 0.0000003 );
   GenTimeSpanFromHours( 0.0012345 );
   GenTimeSpanFromHours( 12.3456789 );
   GenTimeSpanFromHours( 123456.7898765 );
   GenTimeSpanFromHours( 0.0002777 );
   GenTimeSpanFromHours( 0.0166666 );
   GenTimeSpanFromHours( 1 );
   GenTimeSpanFromHours( 24 );
   GenTimeSpanFromHours( 500.3389445 );
}

/*
This example of TimeSpan::FromHours( double )
generates the following output.

            FromHours          TimeSpan
            ---------          --------
                2E-07          00:00:00.0010000
                3E-07          00:00:00.0010000
            0.0012345          00:00:04.4440000
           12.3456789          12:20:44.4440000
       123456.7898765     5144.00:47:23.5550000
            0.0002777          00:00:01
            0.0166666          00:01:00
                    1          01:00:00
                   24        1.00:00:00
          500.3389445       20.20:20:20.2000000
*/

// Example of the TimeSpan.FromHours( double ) method.
using System;

class FromHoursDemo
{
    static void GenTimeSpanFromHours( double hours )
    {
        // Create a TimeSpan object and TimeSpan string from 
        // a number of hours.
        TimeSpan    interval = TimeSpan.FromHours( hours );
        string      timeInterval = interval.ToString( );

        // Pad the end of the TimeSpan string with spaces if it 
        // does not contain milliseconds.
        int pIndex = timeInterval.IndexOf( ':' );
        pIndex = timeInterval.IndexOf( '.', pIndex );
        if( pIndex < 0 )   timeInterval += "        ";

        Console.WriteLine( "{0,21}{1,26}", hours, timeInterval );
    } 

    static void Main( )
    {
        Console.WriteLine(
            "This example of TimeSpan.FromHours( double )\n" +
            "generates the following output.\n" );
        Console.WriteLine( "{0,21}{1,18}",
            "FromHours", "TimeSpan" );
        Console.WriteLine( "{0,21}{1,18}", 
            "---------", "--------" );

        GenTimeSpanFromHours( 0.0000002 );
        GenTimeSpanFromHours( 0.0000003 );
        GenTimeSpanFromHours( 0.0012345 );
        GenTimeSpanFromHours( 12.3456789 );
        GenTimeSpanFromHours( 123456.7898765 );
        GenTimeSpanFromHours( 0.0002777 );
        GenTimeSpanFromHours( 0.0166666 );
        GenTimeSpanFromHours( 1 );
        GenTimeSpanFromHours( 24 );
        GenTimeSpanFromHours( 500.3389445 );
    } 
} 

/*
This example of TimeSpan.FromHours( double )
generates the following output.

            FromHours          TimeSpan
            ---------          --------
                2E-07          00:00:00.0010000
                3E-07          00:00:00.0010000
            0.0012345          00:00:04.4440000
           12.3456789          12:20:44.4440000
       123456.7898765     5144.00:47:23.5550000
            0.0002777          00:00:01
            0.0166666          00:01:00
                    1          01:00:00
                   24        1.00:00:00
          500.3389445       20.20:20:20.2000000
*/

// Example of the TimeSpan.FromHours( double ) method.
open System

let genTimeSpanFromHours hours =
    // Create a TimeSpan object and TimeSpan string from 
    // a number of hours.
    let interval = TimeSpan.FromHours hours
    let timeInterval = string interval

    // Pad the end of the TimeSpan string with spaces if it 
    // does not contain milliseconds.
    let pIndex = timeInterval.IndexOf ':'
    let pIndex = timeInterval.IndexOf('.', pIndex)
    let timeInterval =
        if pIndex < 0 then timeInterval + "        "
        else timeInterval

    printfn $"{hours,21}{timeInterval,26}"

printfn "This example of TimeSpan.FromHours( double )\ngenerates the following output.\n"
printfn "%21s%18s" "FromHours" "TimeSpan"
printfn "%21s%18s" "---------" "--------"

genTimeSpanFromHours 0.0000002
genTimeSpanFromHours 0.0000003
genTimeSpanFromHours 0.0012345
genTimeSpanFromHours 12.3456789
genTimeSpanFromHours 123456.7898765
genTimeSpanFromHours 0.0002777
genTimeSpanFromHours 0.0166666
genTimeSpanFromHours 1
genTimeSpanFromHours 24
genTimeSpanFromHours 500.3389445

(*
This example of TimeSpan.FromHours( double )
generates the following output.

            FromHours          TimeSpan
            ---------          --------
                2E-07          00:00:00.0010000
                3E-07          00:00:00.0010000
            0.0012345          00:00:04.4440000
           12.3456789          12:20:44.4440000
       123456.7898765     5144.00:47:23.5550000
            0.0002777          00:00:01
            0.0166666          00:01:00
                    1          01:00:00
                   24        1.00:00:00
          500.3389445       20.20:20:20.2000000
*)

' Example of the TimeSpan.FromHours( Double ) method.
Module FromHoursDemo

    Sub GenTimeSpanFromHours( hours As Double )

        ' Create a TimeSpan object and TimeSpan string from 
        ' a number of hours.
        Dim interval As TimeSpan = _
            TimeSpan.FromHours( hours )
        Dim timeInterval As String = interval.ToString( )

        ' Pad the end of the TimeSpan string with spaces if it 
        ' does not contain milliseconds.
        Dim pIndex As Integer = timeInterval.IndexOf( ":"c )
        pIndex = timeInterval.IndexOf( "."c, pIndex )
        If pIndex < 0 Then  timeInterval &= "        "

        Console.WriteLine( "{0,21}{1,26}", hours, timeInterval )
    End Sub 

    Sub Main( )

        Console.WriteLine( "This example of " & _
            "TimeSpan.FromHours( Double )" & _
            vbCrLf & "generates the following output." & vbCrLf )
        Console.WriteLine( "{0,21}{1,18}", _
            "FromHours", "TimeSpan" )    
        Console.WriteLine( "{0,21}{1,18}", _
            "---------", "--------" )    

        GenTimeSpanFromHours( 0.0000002 )
        GenTimeSpanFromHours( 0.0000003 )
        GenTimeSpanFromHours( 0.0012345 )
        GenTimeSpanFromHours( 12.3456789 )
        GenTimeSpanFromHours( 123456.7898765 )
        GenTimeSpanFromHours( 0.0002777 )
        GenTimeSpanFromHours( 0.0166666 )
        GenTimeSpanFromHours( 1 )
        GenTimeSpanFromHours( 24 )
        GenTimeSpanFromHours( 500.3389445 )
    End Sub 
End Module 

' This example of TimeSpan.FromHours( Double )
' generates the following output.
' 
'             FromHours          TimeSpan
'             ---------          --------
'                 2E-07          00:00:00.0010000
'                 3E-07          00:00:00.0010000
'             0.0012345          00:00:04.4440000
'            12.3456789          12:20:44.4440000
'        123456.7898765     5144.00:47:23.5550000
'             0.0002777          00:00:01
'             0.0166666          00:01:00
'                     1          01:00:00
'                    24        1.00:00:00
'           500.3389445       20.20:20:20.2000000

Commenti

Il parametro value viene convertito in millisecondi, che viene convertito in tick e tale numero di tick viene usato per inizializzare il nuovo TimeSpan. Pertanto, value verrà considerato accurato solo al millisecondo più vicino. Si noti che, a causa della perdita di precisione del tipo di dati Double, questa conversione può generare un OverflowException per i valori vicini a ma ancora nell'intervallo di MinValue o MaxValue. Ad esempio, questo causa un OverflowException nel tentativo seguente di creare un'istanza di un oggetto TimeSpan.

// The following throws an OverflowException at runtime
TimeSpan maxSpan = TimeSpan.FromHours(TimeSpan.MaxValue.TotalHours);

// The following throws an OverflowException at runtime
let maxSpan = TimeSpan.FromHours TimeSpan.MaxValue.TotalHours

' The following throws an OverflowException at runtime
Dim maxSpan As TimeSpan = TimeSpan.FromHours(TimeSpan.MaxValue.TotalHours)

Vedi anche

• Double
• FromTicks(Int64)
• FromMilliseconds(Double)
• FromSeconds(Double)
• FromMinutes(Double)
• FromDays(Double)