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DateTime.MaxValue Field

Definition

Represents the largest possible value of DateTime. This field is read-only.

public: static initonly DateTime MaxValue;
public static readonly DateTime MaxValue;
 staticval mutable MaxValue : DateTime
Public Shared ReadOnly MaxValue As DateTime 

Field Value

Examples

The following example instantiates a DateTime object by passing its constructor an Int64 value that represents a number of ticks. Before invoking the constructor, the example ensures that this value is greater than or equal to DateTime.MinValue.Ticks and less than or equal to DateTime.MaxValue.Ticks. If not, it throws an ArgumentOutOfRangeException.

// Attempt to assign an out-of-range value to a DateTime constructor.
long numberOfTicks = Int64.MaxValue;
DateTime validDate;

// Validate the value.
if (numberOfTicks >= DateTime.MinValue.Ticks &&
    numberOfTicks <= DateTime.MaxValue.Ticks)
   validDate = new DateTime(numberOfTicks);
else if (numberOfTicks < DateTime.MinValue.Ticks)
   Console.WriteLine("{0:N0} is less than {1:N0} ticks.",
                     numberOfTicks,
                     DateTime.MinValue.Ticks);
else
   Console.WriteLine("{0:N0} is greater than {1:N0} ticks.",
                     numberOfTicks,
                     DateTime.MaxValue.Ticks);
// The example displays the following output:
//   9,223,372,036,854,775,807 is greater than 3,155,378,975,999,999,999 ticks.
// Attempt to assign an out-of-range value to a DateTime constructor.
let numberOfTicks = Int64.MaxValue

// Validate the value.
if numberOfTicks >= DateTime.MinValue.Ticks &&
   numberOfTicks <= DateTime.MaxValue.Ticks then
    let validDate = DateTime numberOfTicks
    ()
elif numberOfTicks < DateTime.MinValue.Ticks then
    printfn $"{numberOfTicks:N0} is less than {DateTime.MinValue.Ticks:N0} ticks."
else
    printfn $"{numberOfTicks:N0} is greater than {DateTime.MaxValue.Ticks:N0} ticks."
// The example displays the following output:
//   9,223,372,036,854,775,807 is greater than 3,155,378,975,999,999,999 ticks.
' Attempt to assign an out-of-range value to a DateTime constructor.
Dim numberOfTicks As Long = Int64.MaxValue
Dim validDate As Date

' Validate the value.
If numberOfTicks >= Date.MinValue.Ticks And _
   numberOfTicks <= Date.MaxValue.Ticks Then
   validDate = New Date(numberOfTicks)
ElseIf numberOfTicks < Date.MinValue.Ticks Then
   Console.WriteLine("{0:N0} is less than {1:N0} ticks.", 
                     numberOfTicks, 
                     DateTime.MinValue.Ticks)      
Else                                                   
   Console.WriteLine("{0:N0} is greater than {1:N0} ticks.", 
                     numberOfTicks, 
                     DateTime.MaxValue.Ticks)     
End If
' The example displays the following output:
'   9,223,372,036,854,775,807 is greater than 3,155,378,975,999,999,999 ticks.

Remarks

The value of this constant is equivalent to 23:59:59.9999999 UTC, December 31, 9999 in the Gregorian calendar, exactly one 100-nanosecond tick before 00:00:00 UTC, January 1, 10000.

Some calendars, such as the ThaiBuddhistCalendar, support an upper date range that is earlier than MaxValue. In these cases, trying to access MaxValue in variable assignments or formatting and parsing operations can throw an ArgumentOutOfRangeException. Rather than retrieving the value of DateTime.MaxValue, you can retrieve the value of the specified culture's latest valid date value from the Calendar.MaxSupportedDateTime property.

Applies to

See also