FromDays Method

TimeSpan.FromDays Method

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Returns a TimeSpan that represents a specified number of days, where the specification is accurate to the nearest millisecond.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public static TimeSpan FromDays(
	double value


Type: System.Double
A number of days, accurate to the nearest millisecond.

Return Value

Type: System.TimeSpan
An object that represents value.


value is less than MinValue or greater than MaxValue.


value is Double.PositiveInfinity.


value is Double.NegativeInfinity.


value is equal to Double.NaN.

The value parameter is converted to milliseconds, which is converted to ticks, and that number of ticks is used to initialize the new TimeSpan. Therefore, value will only be considered accurate to the nearest millisecond. Note that, because of the loss of precision of the Double data type, this conversion can cause an OverflowException for values that are near to but still in the range of either MinValue or MaxValue. For example, this causes an OverflowException in the following attempt to instantiate a TimeSpan object.

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

The following code example creates several TimeSpan objects using the FromDays method.

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

class Example
   static void GenTimeSpanFromDays(System.Windows.Controls.TextBlock outputBlock, double days)
      // Create a TimeSpan object and TimeSpan string from 
      // a number of days.
      TimeSpan interval = TimeSpan.FromDays(days);
      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 += "        ";

      outputBlock.Text += String.Format("{0,21}{1,26}", days, timeInterval) + "\n";

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
      outputBlock.Text += 
          "This example of TimeSpan.FromDays( double )\n" +
          "generates the following output.\n" + "\n";
      outputBlock.Text += String.Format("{0,21}{1,18}",
          "FromDays", "TimeSpan") + "\n";
      outputBlock.Text += String.Format("{0,21}{1,18}",
          "--------", "--------") + "\n";

      GenTimeSpanFromDays(outputBlock, 0.000000006);
      GenTimeSpanFromDays(outputBlock, 0.000000017);
      GenTimeSpanFromDays(outputBlock, 0.000123456);
      GenTimeSpanFromDays(outputBlock, 1.234567898);
      GenTimeSpanFromDays(outputBlock, 12345.678987654);
      GenTimeSpanFromDays(outputBlock, 0.000011574);
      GenTimeSpanFromDays(outputBlock, 0.000694444);
      GenTimeSpanFromDays(outputBlock, 0.041666666);
      GenTimeSpanFromDays(outputBlock, 1);
      GenTimeSpanFromDays(outputBlock, 20.84745602);

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

             FromDays          TimeSpan
             --------          --------
                6E-09          00:00:00.0010000
              1.7E-08          00:00:00.0010000
          0.000123456          00:00:10.6670000
          1.234567898        1.05:37:46.6660000
      12345.678987654    12345.16:17:44.5330000
           1.1574E-05          00:00:01
          0.000694444          00:01:00
          0.041666666          01:00:00
                    1        1.00:00:00
          20.84745602       20.20:20:20.2000000

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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