In this tutorial, you shall learn about While loop statement in Kotlin, its syntax, and how to use While statement to execute a task repeatedly in a loop, with examples.

Kotlin While loop

While Loop statement is used to execute a block of code repeatedly based on a condition.

In this tutorial, we will learn the syntax of While Loop statement, and its usage with the help of example programs.

Syntax

The syntax of While Loop statement is

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while (condition) {
    statements
}
  • while: Kotlin keyword.
  • condition: a boolean expression, or something that evaluates to a boolean value.
  • statements: one or more Kotlin statements. This can be empty as well, if necessary.
  • () parenthesis enclose the condition, and {} curly braces enclose the while loop body.

Examples

1. Print numbers from 1 to N using While Loop

In this following program, we will use While Loop to print numbers from 1 to n.

Main.kt

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fun main() {
    var n = 4

    var i = 1
    while(i <= n){
        println(i)
        i++
    }
}

Output

1
2
3
4

2. While Loop with break statement

In this following example, we will use while loop to print numbers from 1 to infinity. We use break statement inside While Loop to break the loop after printing the number 4.

Kotlin Program – example.kt

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fun main() {
    var i = 1
    while(true){
        println(i)
        i++
        if(i > 4)
            break
    }
}

Output

1
2
3
4

Further Reading

Conclusion

In this Kotlin Tutorial, we learned how to use while and do while loops in Kotlin.