contains

operator fun CharSequence.contains(other: CharSequence, ignoreCase: Boolean = false): Boolean(source)

Returns true if this char sequence contains the specified other sequence of characters as a substring.

Since Kotlin

1.0

Parameters

ignoreCase

true to ignore character case when comparing strings. By default false.

Samples

import java.util.Locale
import java.util.regex.Pattern
import kotlin.test.*

fun main() { 
   //sampleStart 
   val string = "Kotlin 2.2.0"
println("\"K\" in string is ${"K" in string}") // true

// The string only contains capital K
println("\"k\" in string is ${"k" in string}") // false
// However, it will be located if the case is ignored
println("string.contains(\"k\", ignoreCase = true) is ${string.contains("k", ignoreCase = true)}") // true

// Every string contains an empty string
println("\"\" in string is ${"" in string}") // true
// The string contains itself ...
println("string in string is ${string in string}") // true
// ... even if it is empty
println("\"\" in \"\" is ${"" in ""}") // true

// String's prefix is shorter than a string, so it can't contain it
println("string in \"Kotlin\" is ${string in "Kotlin"}") // false 
   //sampleEnd
}

operator fun CharSequence.contains(char: Char, ignoreCase: Boolean = false): Boolean(source)

Returns true if this char sequence contains the specified character char.

Since Kotlin

1.0

Parameters

ignoreCase

true to ignore character case when comparing characters. By default false.


inline operator fun CharSequence.contains(regex: Regex): Boolean(source)

Returns true if this char sequence contains at least one match of the specified regular expression regex.

Since Kotlin

1.0