Golang : Determine if time variables have same calendar day

Problem :

You have two or more variables that are of type time.Time and you want to find out if they are the same.

Solution :

If the time.Time variables are exactly the same up to minutes, you can use time.Equal() function to determine of the time objects are the same or not. For example :

 package main

 import (
 "fmt"
 "time"
 )

 func main() {

 date1 := time.Date(2015, time.November, 24, 23, 0, 0, 0, time.UTC)

 date2 := time.Date(2015, time.November, 24, 23, 0, 0, 0, time.UTC)

 fmt.Println("Date1 is the same as date2? : ", date2.Equal(date1))
 }

Output :

Date1 is the same as date2 : true

However, the above method will become false if the hours, minutes or seconds are not equal. If you are looking to determine if the variables have the same calendar day, then you will need to break the time.Time variable into day, month and year for comparison.

 package main

 import (
 "fmt"
 "time"
 )

 func main() {

 date1 := time.Date(2015, time.November, 24, 23, 0, 0, 0, time.UTC)

 date2 := time.Date(2015, time.November, 24, 11, 0, 0, 0, time.UTC)

 // will become false, because of slight difference in hours !!
 fmt.Println("Date1 is the same as date 2? : ", date2.Equal(date1))

 //year1, month1, day1 := date1.Date()
 //year2, month2, day2 := date2.Date()

 if date1.Day() == date2.Day() {
 fmt.Println("Day 1 is : ", date1)
 fmt.Println("Day 2 is : ", date2)
 fmt.Println("and they have the same calendar day eventhough they have different hours!")
 }
 }

Output :

Date1 is the same as date 2? : false

Day 1 is : 2015-11-24 23:00:00 +0000 UTC

Day 2 is : 2015-11-24 11:00:00 +0000 UTC

and they have the same calendar day even though they have different hours!

References :

https://www.socketloop.com/references/golang-time-time-equal-function-example