How to Check if String is Empty in Kotlin?

In this tutorial, you shall learn how to check if given string is empty in Kotlin, using String.isEmpty() function, with examples.

Kotlin – Check if String is Empty

To check if string is empty in Kotlin, call isEmpty() method on this string. The method returns a boolean value of true, if the string is empty, or false if the string is not empty.

Syntax

The syntax of isEmpty() method is

fun CharSequence.isEmpty(): Boolean

Since isEmpty() returns a boolean value, we can use this as a condition in Kotlin If-Else statement.

Examples

In the following example, we take a string in str and check if this string is empty or not using isEmpty().

Main.kt

fun main(args: Array<String>) {
    var str = ""
    if (str.isEmpty()) {
        println("The string is empty.")
    } else {
        println("The string is not empty.")
    }
}

Output

The string is empty.

Now, let us take a non-empty string in str, and find the output.

Main.kt

fun main(args: Array<String>) {
    var str = "hello world"
    if (str.isEmpty()) {
        println("The string is empty.")
    } else {
        println("The string is not empty.")
    }
}

Output

The string is not empty.

Conclusion

In this Kotlin Tutorial, we learned how to check if given string is empty or not using String.isEmpty(), with examples.