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COleDateTime::GetStatus

Gets the status (validity) of a given COleDateTime object.

DateTimeStatus GetStatus( ) const throw( );

Return Value

Returns the status of this COleDateTime value. If you call GetStatus on a COleDateTime object constructed with the default, it will return valid. If you call GetStatus on a COleDateTime object initialized with the constructor set to null, GetStatus will return null. See Remarks for more information.

Remarks

The return value is defined by the DateTimeStatus enumerated type, which is defined within the COleDateTime class.

enum DateTimeStatus

{

error = -1,

valid = 0,

invalid = 1, // Invalid date (out of range, etc.)

null = 2, // Literally has no value

};

For a brief description of these status values, see the following list:

  • COleDateTime::error   Indicates that an error occurred while attempting to obtain part of the date/time value.

  • COleDateTime::valid   Indicates that this COleDateTime object is valid.

  • COleDateTime::invalid   Indicates that this COleDateTime object is invalid; that is, its value may be incorrect.

  • COleDateTime::null   Indicates that this COleDateTime object is null, that is, that no value has been supplied for this object. (This is "null" in the database sense of "having no value," as opposed to the C++ NULL.)

The status of a COleDateTime object is invalid in the following cases:

  • If its value is set from a VARIANT or COleVariant value that could not be converted to a date/time value.

  • If its value is set from a time_t, SYSTEMTIME, or FILETIME value that could not be converted to a valid date/time value.

  • If its value is set by SetDateTime with invalid parameter values.

  • If this object has experienced an overflow or underflow during an arithmetic assignment operation, namely, += or -=.

  • If an invalid value was assigned to this object.

  • If the status of this object was explicitly set to invalid using SetStatus.

For more information about the operations that may set the status to invalid, see the following member functions:

For more information about the bounds for COleDateTime values, see the article Date and Time: Automation Support.

Example

COleDateTime t;

// this one is a leap year
t.SetDateTime(2000, 2, 29, 5, 0, 0);
ASSERT(t.GetStatus() == COleDateTime::valid);

// this date isn't valid
t.SetDateTime(1925, 2, 30, 5, 0, 0);
ASSERT(t.GetStatus() == COleDateTime::invalid);

// the only way to set null is to set null!
t.SetStatus(COleDateTime::null);
ASSERT(t.GetStatus() == COleDateTime::null);   

Requirements

Header: atlcomtime.h

See Also

Reference

COleDateTime Class

Hierarchy Chart

COleDateTime::SetStatus

COleDateTime::m_status