This class provides methods for managing the date and time values associated with the creation, access and modification of files. The methods and data of this class are frequently used in conjunction with CFileTimeSpan objects, which deal with relative time values.
The date and time value is stored as a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601. A nanosecond is one-billionth of a second.
The following static const member variables are provided to simplify calculations (number of 100-nanosecond intervals):
CFileTime_Millisecond 10000ull
CFileTime_Second CFileTime_Millisecond * 1000
CFileTime_Minute CFileTime_Second * 60
CFileTime_Hour CFileTime_Minute * 60
CFileTime_Day CFileTime_Hour * 24
CFileTime_Week CFileTime_Day * 7
Note: Not all file systems can record creation and last access time and not all file systems record them in the same manner. For example, on the Windows NT FAT file system, create time has a resolution of 10 milliseconds, write time has a resolution of 2 seconds, and access time has a resolution of 1 day (the access date). On NTFS, access time has a resolution of 1 hour. Furthermore, FAT records times on disk in local time, but NTFS records times on disk in UTC.
| Name | Description |
|---|---|
| Constructors | Create new CFileTime objects initialized to the specified value. |
| CAST Operator | Returns the CFileTime value as a long integer. |
| LET Operator | Assigns a value to a CFileTime object. |
| Operators | Adds, subtracts or compares CFileTime objects. |
| DateString | Retuns the date as a string based on the specified mask, e.g. "dd-MM-yyyy". |
| Day | Returns the number of 100-nanosecond intervals that make up one day. |
| Format | Converts a CFileTime object to a string. |
| GetAsFileTime | Returns the time as a FILETIME structure. |
| GetAsSystemTime | Returns the time as a SYSTEMTIME structure. |
| GetCurrentTime | Returns a CFileTime object that represents the current system date and time. |
| GetTime | Returns the value of the CFileTime object. |
| Hour | Returns the number of 100-nanosecond intervals that make up one hour. |
| LocalToUTC | Converts a local file time to a file time based on the Coordinated Universal Time (UTC). |
| Millisecond | Returns the number of 100-nanosecond intervals that make up one millisecond. |
| Minute | Returns the number of 100-nanosecond intervals that make up one minute. |
| Second | Returns the number of 100-nanosecond intervals that make up one second. |
| SetTime | Sets the date and time of this CFileTime object. |
| TimeString | Retuns the time as a string based on the specified mask, e.g. "dd-MM-yyyy". |
| UTCToLocal | Converts time based on the Coordinated Universal Time (UTC) to local file time. |
| Week | Returns the number of 100-nanosecond intervals that make up one week. |
This class provides methods for managing relative periods of time often encountered when performing operations concerning when a file was created, last accessed or last modified. The methods of this class are frequently used in conjunction with CFileTime class objects.
The CFileTimeSpan object can be created using an existing CFileTimeSpan object, or expressed as a 64-bit value. The default constructor sets the time span to 0.
| Name | Description |
|---|---|
| Constructors | Create new CFileTimeSpan objects initialized to the specified value. |
| CAST Operator | Returns the CFileTimeSpan value as a long integer. |
| LET Operator | Assigns a value to a CFileTimeSpan object. |
| Operators | Adds, subtracts or compares CFileTimeSpan objects. |
| Day | Returns the number of 100-nanosecond intervals that make up one day. |
| GetTimeSpan | Returns the value of the CFileTimeSpan object. |
| Hour | Returns the number of 100-nanosecond intervals that make up one hour. |
| Millisecond | Returns the number of 100-nanosecond intervals that make up one millisecond. |
| Minute | Returns the number of 100-nanosecond intervals that make up one minute. |
| Second | Returns the number of 100-nanosecond intervals that make up one second. |
| SetTimeSpan | Sets the date and time of this CFileTimeSpan object. |
| Week | Returns the number of 100-nanosecond intervals that make up one week. |
Create new CFileTime objects initialized to the specified value.
CONSTRUCTOR CFileTime
CONSTRUCTOR CFileTime (BYVAL nSpan AS ULONGLONG)
CONSTRUCTOR CFileTime (BYREF ft AS FILETIME)
CONSTRUCTOR CFileTime (BYREF st AS SYSTEMTIME)
| Parameter | Description |
|---|---|
| nSpan | A date and time expressed as a 64-bit value. |
| ft | A FILETIME structure. |
| st | A SYSTEMTIME structure. |
DIM cft AS CFileTime = CFileTime().GetCurrentTime()
DIM cft AS CFileTime = AfxLocalFileTime
print cft.GetTime
DIM cft AS CFileTime = AfxLocalSystemTime
print cft.GetTime
Create new CFileTimeSpan objects initialized to the specified value.
CONSTRUCTOR CFileTimeSpan
CONSTRUCTOR CFileTimeSpan (BYVAL nSpan AS ULONGLONG)
CONSTRUCTOR CFileTimeSpan (BYREF cSpan AS CFileTimeSpan)
| Parameter | Description |
|---|---|
| nSpan | A period of time in milliseconds. |
| cSpan | A CFileTimeSpan object. |
DIM cSpan AS CFileTimeSpan = CFileTime_Day
Returns the CFileTime value as a long integer.
OPERATOR CAST () AS LONGLONG
DIM cft AS CFileTime = CFileTime().GetCurrentTime()
DIM nTime AS LONGLONG = cft
print nTime
DIM cft AS CFileTime = CFileTime().GetCurrentTime()
DIM cft2 AS CFileTime = cft
Returns the CFileTimeSpan value as a long integer.
OPERATOR CAST () AS LONGLONG
Assigns a value to a CFileTime object.
OPERATOR LET (BYVAL nTime AS ULONGLONG)
OPERATOR LET (BYREF ft AS FILETIME)
OPERATOR LET (BYREF st AS SYSTEMTIME)
| Parameter | Description |
|---|---|
| nTime | A date and time expressed as a 64-bit value. |
| ft | A FILETIME structure. |
| st | A SYSTEMTIME structure. |
DIM cft AS CFileTime
cft = AfxLocalFileTime
print cft.GetTime
DIM cft AS CFileTime
cft = AfxLocalSystemTime
print cft.GetTime
Assigns a value to a CFileTimeSpan object.
OPERATOR LET (BYVAL nSpan AS LONGLONG)
OPERATOR LET (BYREF cSpan AS CFileTimeSpan)
| Parameter | Description |
|---|---|
| nSpan | A period of time in milliseconds. |
| cSpan | A CFileTimeSpan object. |
Adds, subtracts or compares CFileTime objects.
OPERATOR + (BYREF dt AS CFileTime, BYREF dateSpan AS CFileTimeSpan) AS CFileTime
OPERATOR - (BYREF dt AS CFileTime, BYREF dateSpan AS CFileTimeSpan) AS CFileTime
OPERATOR - (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS CFileTimeSpan
OPERATOR += (BYREF dateSpan AS CFileTimeSpan)
OPERATOR -= (BYREF dateSpan AS CFileTimeSpan)
OPERATOR = (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS BOOLEAN
OPERATOR <> (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS BOOLEAN
OPERATOR < (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS BOOLEAN
OPERATOR > (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS BOOLEAN
OPERATOR <= (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS BOOLEAN
OPERATOR >= (BYREF dt1 AS CFileTime, BYREF dt2 AS CFileTime) AS BOOLEAN
Adds, subtracts or compares CFileTimeSpan objects.
OPERATOR + (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS CFileTimeSpan
OPERATOR - (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS CFileTimeSpan
OPERATOR += (BYREF dateSpan AS CFileTimeSpan)
OPERATOR -= (BYREF dateSpan AS CFileTimeSpan)
OPERATOR = (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS BOOLEAN
OPERATOR <> (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS BOOLEAN
OPERATOR < (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS BOOLEAN
OPERATOR > (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS BOOLEAN
OPERATOR <= (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS BOOLEAN
OPERATOR >= (BYREF cSpan1 AS CFileTimeSpan, BYREF cSpan2 AS CFileTimeSpan) AS BOOLEAN
Returns the number of 100-nanosecond intervals that make up one day.
FUNCTION Day () AS ULONGLONG
Returns the number of 100-nanosecond intervals that make up one hour.
FUNCTION Hour () AS ULONGLONG
Returns the number of 100-nanosecond intervals that make up one millisecond.
FUNCTION Millisecond () AS ULONGLONG
Returns the number of 100-nanosecond intervals that make up one minute.
FUNCTION Minute () AS ULONGLONG
Returns the number of 100-nanosecond intervals that make up one second.
FUNCTION Second () AS ULONGLONG
Returns the number of 100-nanosecond intervals that make up one week.
FUNCTION Week () AS ULONGLONG
Retuns the date as a string based on the specified mask, e.g. "dd-MM-yyyy".
FUNCTION DateString (BYREF wszMask AS WSTRING, BYVAL lcid AS LCID = LOCALE_USER_DEFAULT) AS CWSTR
| Parameter | Description |
|---|---|
| wszMask | A picture string that is used to form the date. The format types "d", and "y" must be lowercase and the letter "M" must be uppercase. For example, to get the date string "Wed, Aug 31 94", the application uses the picture string "ddd',' MMM dd yy". |
| lcid | Optional. The language identifier used for the conversion. Default is LOCALE_USER_DEFAULT. |
The following table defines the format types used to represent days.
| Format type | Meaning |
|---|---|
| d | Day of the month as digits without leading zeros for single-digit days. |
| dd | Day of the month as digits with leading zeros for single-digit days. |
| ddd | Abbreviated day of the week, for example, "Mon" in English (United States). |
| dddd | Day of the week. |
The following table defines the format types used to represent months.
| Format type | Meaning |
|---|---|
| M | Month as digits without leading zeros for single-digit months. |
| MM | Month as digits with leading zeros for single-digit months. |
| MMM | Abbreviated month, for example, "Nov" in English (United States). |
| MMMM | Month value, for example, "November" for English (United States), and "Noviembre" for Spanish (Spain). |
The following table defines the format types used to represent years.
| Format type | Meaning |
|---|---|
| y | Year represented only by the last digit. |
| yy | Year represented only by the last two digits. A leading zero is added for single-digit years. |
| yyyy | Year represented by a full four or five digits, depending on the calendar used. Thai Buddhist and Korean calendars have five-digit years. The "yyyy" pattern shows five digits for these two calendars, and four digits for all other supported calendars. Calendars that have single-digit or two-digit years, such as for the Japanese Emperor era, are represented differently. A single-digit year is represented with a leading zero, for example, "03". A two-digit year is represented with two digits, for example, "13". No additional leading zeros are displayed. |
| yyyyy | Behaves identically to "yyyy". |
The formatted date.
Retuns the time as a string based on the specified mask, e.g. "hh':'mm':'ss".
FUNCTION TimeString (BYREF wszMask AS WSTRING, BYVAL lcid AS LCID = LOCALE_USER_DEFAULT) AS CWSTR
| Parameter | Description |
|---|---|
| ft | A FILETIME structure. |
| wszMask | A picture string that is used to form the time. |
| lcid | Optional. The language identifier used for the conversion. Default is LOCALE_USER_DEFAULT. |
The application can use the following elements to construct a format picture string. If spaces are used to separate the elements in the format string, these spaces appear in the same location in the output string. The letters must be in uppercase or lowercase as shown, for example, "ss", not "SS". Characters in the format string that are enclosed in single quotation marks appear in the same location and unchanged in the output string.
| Picture | Meaning |
|---|---|
| h | Hours with no leading zero for single-digit hours; 12-hour clock |
| hh | Hours with leading zero for single-digit hours; 12-hour clock |
| H | Hours with no leading zero for single-digit hours; 24-hour clock |
| HH | Hours with leading zero for single-digit hours; 24-hour clock |
| m | Minutes with no leading zero for single-digit minutes |
| mm | Minutes with leading zero for single-digit minutes |
| s | Seconds with no leading zero for single-digit seconds |
| ss | Seconds with leading zero for single-digit seconds |
| t | One character time marker string, such as A or P |
| tt | Multi-character time marker string, such as AM or PM |
The formatted time.
Converts a CFileTime object to a string.
FUNCTION Format (BYREF wszFmt AS WSTRING) AS CWSTR
Formatting codes:
| Code | Meaning |
|---|---|
| %a | Abbreviated weekday name |
| %A | Full weekday name |
| %b | Abbreviated month name |
| %B | Full month name |
| %c | Date and time representation appropriate for locale |
| %d | Day of month as decimal number (01 – 31) |
| %H | Hour in 24-hour format (00 – 23) |
| %I | Hour in 12-hour format (01 – 12) |
| %j | Day of year as decimal number (001 – 366) |
| %m | Month as decimal number (01 – 12) |
| %M | Minute as decimal number (00 – 59) |
| %p | Current locale's A.M./P.M. indicator for 12-hour clock |
| %S | Second as decimal number (00 – 59) |
| %U | Week of year as decimal number, with Sunday as first day of week (00 – 53) |
| %w | Weekday as decimal number (0 – 6; Sunday is 0) |
| %W | Week of year as decimal number, with Monday as first day of week (00 – 53) |
| %x | Date representation for current locale |
| %X | Time representation for current locale |
| %y | Year without century, as decimal number (00 – 99) |
| %Y | Year with century, as decimal number |
| %z, %Z | Either the time-zone name or time zone abbreviation, depending on registry settings; no characters if time zone is unknown |
| %% | Percent sign |
The # flag may prefix any formatting code. In that case, the meaning of the format code is changed as follows.
Formats the value by using the format string which contains special formatting codes that are preceded by a percent sign (%).
print cft.Format("%A, %B %d, %Y %H:%M:%S")
DIM cft AS CFileTime
cft = AfxLocalFileTime
print cft.Format("%A, %B %d, %Y %H:%M:%S")
Returns the time as a FILETIME structure.
FUNCTION GetAsFileTime () AS FILETIME
Returns the time as a SYSTEMTIME structure.
FUNCTION GetAsSystemTime () AS SYSTEMTIME
Returns a CFileTime object that represents the current system date and time.
FUNCTION GetCurrentTime () AS CFileTime
Returns the value of the CFileTime object.
FUNCTION GetTime () AS LONGLONG
DIM cft AS CFileTime = CFileTime().GetCurrentTime()
print cft.GetTime
Sets the date and time of this CFileTime object
FUNCTION SetTime (BYVAL nTime AS ULONGLONG)
| Parameter | Description |
|---|---|
| nTime | The date and time expressed as a 64-bit value. |
Converts a local file time to a file time based on the Coordinated Universal Time (UTC).
FUNCTION LocalToUTC () AS CFileTime
Converts time based on the Coordinated Universal Time (UTC) to local file time.
FUNCTION UTCToLocal () AS CFileTime
Returns the value of the CFileTimeSpan object.
FUNCTION GetTimeSpan () AS LONGLONG
Sets the date and time of this CFileTimeSpan object.
FUNCTION SetTimeSpan (BYVAL nSpan AS LONGLONG)
| Parameter | Description |
|---|---|
| nSpan | The new value for the time span in milliseconds. |