Kotlin do-while Loop with examples

A do-while loop is similar to while loop except that it checks the condition at the end of iteration. A do-while loop will at least run once even if the given condition is false.

Kotlin do-while loop Example

/**
 * created by Chaitanya for Beginnersbook.com
 */

package beginnersbook

fun main(args : Array<String>){

    var num = 100
    do {
        println("Loop: $num")
        num++
    }
    while (num<=105)
}

Output:

A do-while loop at least run once

As I mentioned in the beginning of this guide, a do-while loop will at least run once even if the given condition returns false. This happens because the do-while loop checks the condition after execution of the loop body.

/**
 * created by Chaitanya for Beginnersbook.com
 */

package beginnersbook

fun main(args : Array<String>){

    var num = 100
    do {
        println("Loop: $num")
        num++
    }
    while (false)
}

Output:

Infinite do while loop in Kotlin

A do while loop that runs infinitely and never stops is called infinite do while loop. Lets look at the few examples of infinite do while loop.

Example 1:

var num = 100
do {
    println("Loop: $num")
    num++   
}
while (true)

Example 2:

var num = 100
do {
    println("Loop: $num")
    num--  
}
while (num<=105)

Example 3:

var num = 105
do {
    println("Loop: $num")
    num++
}
while (num>=100)