Expert Advisor Programming by Andrew R. Young

Working with Time and Date
formats for datetime constants: the MQL Reference topic Basics – Data Types – Datetime constants
has more information. We'll use the format presented above, since it is the only one that can be
easily converted.
To convert a datetime variable to a string constant, use the function TimeToStr(). Here is the
syntax:
string TimeToStr(datetime Time, int Output = TIME_DATE|TIME_MINUTES);
• Time – A datetime variable expressed as the number of seconds elapsed since January 1,
1970.
• Output – An optional parameter that outputs the constant as date only, hour and minute
only; hour, minute and seconds; or any combination of date and time. Valid input values are :
◦ TIME_DATE – Outputs the date, for example, 2009.06.15
◦ TIME_MINUTES – Outputs hour and minute, for example, 05:30
◦ TIME_SECONDS – Outputs hour, minute and seconds, for example, 05:30:45
To output the string constant in the default yyyy.mm.dd hh:mm format, leave Output blank. If you
only want the date, or the hour and minute (or seconds), use the appropriate argument. In this
example, we'll assume that StartTime is equal to 2009.06.15 05:30:45.
TimeToStr(StartTime,TIME_DATE) // Returns "2009.06.15"
TimeToStr(StartTime,TIME_SECONDS) // Returns "05:30:45"
TimeToStr(StartTime,TIME_MINUTES) // Returns "05:30"
TimeToStr(StartTime,TIME_DATE|TIME_SECONDS) // Returns "2009.06.15 05:30:45"
TimeToStr(StartTime) // Returns "2009.06.15 05:30"
We can construct a datetime constant using string concatenation, and convert it to a datetime
variable using the function StrToTime(). The syntax is identical to TimeToStr() above, but without
the Output parameter. The string constant must be in the format yyyy.mm.dd hh:mm to be converted
correctly.
Here's an example of how we can assemble a datetime constant using integers, convert those
integers to string format, and convert the string to a datetime variable. First, we'll declare some
external variables to set a time and date:
extern int UseMonth = 6;
extern int UseDay = 15;
extern int UseHour = 5;
extern int UseMinute = 30;
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