MQL4 Help as One File:

Date and Time

This is the group of functions for working with data of datetime type (an integer that represents the number of seconds elapsed from 0 hours of January 1, 1970).

To arrange high-resolution counters and timers, use the GetTickCount() function, which produces values in milliseconds.

Function	Action
TimeCurrent	Returns the last known server time (time of the last quote receipt) in the datetime format
TimeLocal	Returns the local computer time in datetime format
TimeGMT	Returns GMT in datetime format with the Daylight Saving Time by local time of the computer, where the client terminal is running
TimeDaylightSavings	Returns the sign of Daylight Saving Time switch
TimeGMTOffset	Returns the current difference between GMT time and the local computer time in seconds, taking into account DST switch
TimeToStruct	Converts a datetime value into a variable of MqlDateTime structure type
StructToTime	Converts a variable of MqlDateTime structure type into a datetime value
Day	Returns the current day of the month, i.e., the day of month of the last known server time
DayOfWeek	Returns the current zero-based day of the week of the last known server time
DayOfYear	Returns the current day of the year i.e., the day of year of the last known server time
Hour	Returns the hour of the last known server time by the moment of the program start
Minute	Returns the current minute of the last known server time by the moment of the program start
Month	Returns the current month as number, i.e., the number of month of the last known server time
Seconds	Returns the amount of seconds elapsed from the beginning of the current minute of the last known server time by the moment of the program start
TimeDay	Returns the day of month of the specified date
TimeDayOfWeek	Returns the zero-based day of week of the specified date
TimeDayOfYear	Returns the day of year of the specified date
TimeHour	Returns the hour of the specified time
TimeMinute	Returns the minute of the specified time
TimeMonth	Returns the month number of the specified time
TimeSeconds	Returns the amount of seconds elapsed from the beginning of the minute of the specified time
TimeYear	Returns year of the specified date
Year	Returns the current year, i.e., the year of the last known server time

What's new in MQL5

Added the MqlDateTime structure containing eight int type fields:

struct MqlDateTime
  {
   int year;           // year
   int mon;            // month
   int day;            // day
   int hour;           // hour
   int min;            // minutes
   int sec;            // seconds
   int day_of_week;    // day of week (0 - Sunday, 1 - Monday, ..., 6 - Saturday)
   int day_of_year;    // number of a day in a year (January 1 has number 0)
  };

Thus, the new TimeToStruct() and StructToTime() functions allow you to receive and pass data on days, hours, minutes and seconds within a single call.

StringSetCharTimeCurrent