Kotlin: Get file's extension e.g. ".txt"

Question

Is there a standard way to get the extension of a File in Kotlin?

File("a/b/file.txt")

Answer 1

Disclaimer: This is only available on the JVM.

You can find very neat extensions on java.io classes like File in kotlin.io. In order to get the file extension, use the following:

File("a/b/file.txt").extension

This extension property is defined here:

public val File.extension: String
        get() = name.substringAfterLast('.', "")