indexOf

fun CharSequence.indexOf(char: Char, startIndex: Int = 0, ignoreCase: Boolean = false): Int(source)

Returns the index within this string of the first occurrence of the specified character, starting from the specified startIndex.

Return

An index of the first occurrence of char or -1 if none is found.

Parameters

ignoreCase

true to ignore character case when matching a character. By default false.

fun CharSequence.indexOf(string: String, startIndex: Int = 0, ignoreCase: Boolean = false): Int(source)

Returns the index within this char sequence of the first occurrence of the specified string, starting from the specified startIndex.

Return

An index of the first occurrence of string or -1 if none is found.

Samples



import java.util.Locale


import kotlin.test.*
fun main() { 
   //sampleStart 
   fun matchDetails(inputString: String, whatToFind: String, startIndex: Int = 0): String {
    val matchIndex = inputString.indexOf(whatToFind, startIndex)
    return "Searching for '$whatToFind' in '$inputString' starting at position $startIndex: " +
            if (matchIndex >= 0) "Found at $matchIndex" else "Not found"
}

val inputString = "Never ever give up"
val toFind = "ever"

println(matchDetails(inputString, toFind)) // Searching for 'ever' in 'Never ever give up' starting at position 0: Found at 1
println(matchDetails(inputString, toFind, 2)) // Searching for 'ever' in 'Never ever give up' starting at position 2: Found at 6
println(matchDetails(inputString, toFind, 10)) // Searching for 'ever' in 'Never ever give up' starting at position 10: Not found 
   //sampleEnd
}

Parameters

ignoreCase

true to ignore character case when matching a string. By default false.