kotlin-stdlib/kotlin.collections/contains

contains

operator fun <T> Array<out T>.contains(element: T): Boolean(source)

operator fun ByteArray.contains(element: Byte): Boolean(source)

operator fun ShortArray.contains(element: Short): Boolean(source)

operator fun IntArray.contains(element: Int): Boolean(source)

operator fun LongArray.contains(element: Long): Boolean(source)

operator fun BooleanArray.contains(element: Boolean): Boolean(source)

operator fun CharArray.contains(element: Char): Boolean(source)

Returns true if element is found in the array.

operator fun <T> Iterable<T>.contains(element: T): Boolean(source)

Returns true if element is found in the collection.

inline operator fun <K, V> Map<out K, V>.contains(key: K): Boolean(source)

Checks if the map contains the given key.

This method allows to use the x in map syntax for checking whether an object is contained in the map.

Samples



import kotlin.test.*


import java.util.*
fun main() { 
   //sampleStart 
   val map: Map<String, Int> = mapOf("x" to 1)

println("map.contains("x") is ${map.contains("x")}") // true
println(""x" in map is ${"x" in map}") // true

println("map.contains("y") is ${map.contains("y")}") // false
println(""y" in map is ${"y" in map}") // false 
   //sampleEnd
}

operator fun FloatArray.~~contains~~(element: Float): Boolean(source)

operator fun DoubleArray.~~contains~~(element: Double): Boolean(source)

Deprecated

Warning since 1.4

The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'any { it == element }' instead to continue using this behavior, or '.asList().contains(element: T)' to get the same search behavior as in a list.

Replace with

any { it == element }

Returns true if element is found in the array.