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DateTime.AddSeconds Method

Adds the specified number of seconds to the value of this instance.

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

public DateTime AddSeconds (
	double value
public DateTime AddSeconds (
	double value
public function AddSeconds (
	value : double
) : DateTime
Not applicable.



A number of whole and fractional seconds. The value parameter can be negative or positive.

Return Value

A DateTime whose value is the sum of the date and time represented by this instance and the number of seconds represented by value.

Exception typeCondition


The resulting DateTime is less than MinValue or greater than MaxValue.

This method does not change the value of this DateTime. Instead, a new DateTime is returned whose value is the result of this operation.

The fractional part of value is the fractional part of a second. For example, 4.5 is equivalent to 4 seconds, 500 milliseconds, and 0 ticks.

The value parameter is rounded to the nearest millisecond.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0

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