Datetime grouped

 

1. Date and Time Formatting

These functions are used to format dates and times.

• date() — Formats a local date and time according to a specified format.
• date_create() — Creates a new DateTime object.
• date_format() — Formats a DateTime object.
• strftime() — Formats a local time/date according to the specified format (locale-dependent).
• gmdate() — Formats a GMT date and time.
• time() — Returns the current Unix timestamp (seconds since the Unix Epoch).
• getdate() — Returns an associative array containing date information.
• localtime() — Returns an associative array containing local time information.
• microtime() — Returns the current Unix timestamp with microseconds.
• date_create_from_format() — Creates a DateTime object from a specific format.
• date_parse() — Parses a date and time into an array.

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2. Date and Time Parsing and Conversion

These functions are used to parse strings into date/time objects or to convert them into other formats.

• strtotime() — Parses an English textual datetime description into a Unix timestamp.
• date_parse_from_format() — Parses a date/time string into an associative array based on a specific format.
• date_create_from_format() — Creates a DateTime object from a string using a specified format.
• getdate() — Retrieves date information from a timestamp.

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3. Time Zone Functions

These functions help manage and manipulate time zones.

• date_default_timezone_set() — Sets the default time zone for all date/time functions.
• date_default_timezone_get() — Gets the default time zone.
• timezone_open() — Opens a DateTimeZone object.
• timezone_identifiers_list() — Returns a list of all supported time zones.
• timezone_name_get() — Gets the name of the time zone.
• timezone_offset_get() — Gets the offset from UTC for a time zone.
• timezone_transitions_get() — Returns an array of time zone transitions.

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4. Date and Time Arithmetic

These functions are used to add or subtract time and calculate intervals.

• strtotime() — Parses a relative time string (e.g., +1 day, -1 week) and returns a Unix timestamp.
• date_add() — Adds a time interval to a DateTime object.
• date_sub() — Subtracts a time interval from a DateTime object.
• diff() — Returns the difference between two DateTime objects as a DateInterval object.
• date_interval_create_from_date_string() — Creates a DateInterval object from a date string.
• date_modify() — Modifies the DateTime object by adding or subtracting time.

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5. Time and Date Comparisons

These functions are used to compare date and time values.

• date_diff() — Calculates the difference between two DateTime objects.
• date_timestamp_get() — Gets the Unix timestamp from a DateTime object.
• date_timestamp_set() — Sets the Unix timestamp for a DateTime object.
• time() — Returns the current Unix timestamp.

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6. Date and Time Information

These functions are used to retrieve specific parts or elements of a date/time.

• date("Y-m-d H:i:s") — Formats the current date and time.
• gettimeofday() — Returns current Unix timestamp along with microseconds.
• localtime() — Returns an associative array containing local time information.
• gmdate() — Formats a GMT date and time.
• getdate() — Returns an array of date information.

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7. Date and Time Validation

These functions are used to check the validity of a given date or time.

• checkdate() — Validates a Gregorian date (month, day, year).
• is_numeric() — Checks if a value is a valid numeric value for timestamps.
• date_create_from_format() — Parses a date string into a DateTime object, useful for validation.

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8. Date and Time Intervals

These functions deal with intervals between dates and creating intervals.

• date_interval_create_from_date_string() — Creates a DateInterval object from a string (e.g., P1Y2M10DT2H30M).
• date_add() — Adds a DateInterval object to a DateTime object.
• date_sub() — Subtracts a DateInterval object from a DateTime object.
• date_diff() — Calculates the difference between two DateTime objects.
• date_interval_format() — Formats a DateInterval object as a string.

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9. Miscellaneous Functions

These functions provide additional utility when working with date and time.

• time() — Returns the current Unix timestamp.
• microtime() — Returns the current Unix timestamp with microseconds.
• date_default_timezone_set() — Sets the default time zone for all date/time functions.
• date_default_timezone_get() — Gets the default time zone.
• strtotime() — Converts an English textual datetime description into a Unix timestamp.

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