Kotlin for Loop

Kotlin for loop is used to iterate a part of program several times. It iterates through arrays, ranges, collections, or anything that provides for iterate. Kotlin for loop is equivalent to the foreach loop in languages like C#.

Syntax of for loop in Kotlin:

Iterate through array

Let’s see a simple example of iterating the elements of array.

Output:

80  85  60  90  70  

If the body of for loop contains only one single line of statement, it is not necessary to enclose within curly braces {}.

The elements of an array are iterated on the basis of indices (index) of array. For example:

Output:

marks[0]: 80  marks[1]: 85  marks[2]: 60  marks[3]: 90  marks[4]: 70  

Iterate through range

Let’s see an example of iterating the elements of range.

Output:

for (i in 1..5) print(i) = 12345  for (i in 5..1) print(i) =   for (i in 5 downTo 1) print(i) = 54321  for (i in 5 downTo 2) print(i) = 5432  for (i in 1..5 step 2) print(i) = 135  for (i in 5 downTo 1 step 2) print(i) = 531