Date, Time, Time Add and Subtract, and Time Conversion Blocks

These are the various date and time related blocks available in the Time group of the block library:

• date: extracts just the date portion of a date time value

• dateTimeAdd: adds a duration (hrs, mins, or secs) to a dateTime

• dateTimeSub: subtracts a duration (hrs, mins, or secs) from a dateTime

• dateToNumber: converts the date into a number

• dateToString: converts a part of date into a string

• dtToDtAdd: adds one dateTime to another dateTime; results in a duration of minutes or seconds

• dtToDtSub: subtracts one dateTime from another dateTime; results in a duration of minutes or seconds

• now: gets the current dateTime for the host

• siteDateTime: gets the current date and time for the site associated with the target Ref of the bline program

• time: extracts just the time portion of a date time value

• timeToMinutes: converts a time value to a number of minutes 

• timeToTimeAdd: adds one time to another time; results in a duration of minutes

• timeToTimeSub: subtracts one time from another time; results in a duration of minutes

Some blocks have inputs or results in dateTime format, while others in simple time format. Blocks that require a time format input might not work if a dateTime value is used as the input.

dateTime example:  2019-07-04  14:39:15:149   (date and time with milliseconds) 

time example: 14:39:15  (just hours:minutes:seconds)

The Blocks can be found in the Block Library in the Time group.

Date and Time Blocks

These four blocks provide or extract a value of time or dateTime, depending on your usage and need.

date: extracts just the date portion of a date time value

time: extracts just the time portion of a date time value

now: gets the current date and time from the host PC where the program is running

siteDateTime: gets the current date and time for the site associated with the target Ref of the bline program

Time Add and Subtract Blocks

dateTimeAdd: adds a duration (days, hrs, mins, or secs) to a dateTime

dateTimeSub: subtracts a duration (days, hrs, mins, or secs) from a dateTime

dtToDtAdd: adds one dateTime to another dateTime; results in a duration of minutes or seconds. Note: This is not to be considered a traditional add function. Rather, the result is in fact an invert of a subtraction of the two inputs.  Meaning, if the difference is 30 minutes, then the result is written as -30 min. So it is actually subtracting the two inputs and then inverting the math sign of the result.

dtToDtSub: subtracts one dateTime from another dateTime; results in a duration of minutes or seconds

timeToTimeAdd: adds one time to another time; results in a duration of minutes or seconds. Note: This is not to be considered a traditional add function. Rather, the result is in fact an invert of a subtraction of the two inputs.  Meaning, if the difference is 30 minutes, then the result is written as -30 min. So it is actually subtracting the two inputs and then inverting the math sign of the result.

timeToTimeSub: subracts one time from another time; results in a duration of minutes or seconds

Time Conversion Blocks

dateToNumber: converts the date into a number. This block extracts a selected portion of the date and converts it to a number that represents that Year, Month, Day, etc.
As you can see in the example below, we show how to use the block to extract those three entities from the date. You could also get Hour, Minute, or Second if desired.

dateToString: converts a part of date into a string. This block extracts a selected portion of the date and converts it to the actual Month or Day of the week.
In the example below, we show how to use the block to extract those two entities from the date.

timeToMinutes: converts a time value to a number of minutes. In the example below, we have converted current time of 19:20 to 1160 minutes.  Also, you will see that we took minutes and divided it by 60 to get the current hour of the day. That result is 19.33 hours, or 7:20pm (.33 hours is approximately 20 minutes).

Usage Examples

Parking Lot Lights

In the example below, we are using the time block to extract just current time from the now block. Then we are using time subtract blocks to determine if the current time is either 15 minutes before sunset (or less) or 15 minutes after sunrise (or less).  If either of these conditions are true, then we set the Parking Lot Lights to on. In our example below, current time is 20:17 and sunset time is 20:29. Because the difference is less than 15 minutes, the lights are set on.

Another thing we could do with this application is to set the Sunrise, Sunset, and Current Time as Project variables (or global variables), so we wouldn't have to use the weather blocks in every program. We could also package up this lighting application as a Macro in order to use it elsewhere in this project, as well as export it for use in other projects.