Kotlin Strings

String Basics and Templates

A String in Kotlin is an immutable sequence of characters created with double quotes. String templates let you embed expressions directly inside a string using $variableName for simple references or ${expression} for anything more complex.

fun main() {
    val firstName = "Meera"
    val lastName = "Rao"
    val fullName = "$firstName $lastName"

    println("Hello, $fullName!")
    println("Your name has ${fullName.length} characters")
}

Multiline and Raw Strings

Triple-quoted strings (\"\"\"...\"\"\") preserve line breaks and do not require escaping backslashes or quotes, which makes them ideal for multi-line text blocks such as SQL queries or formatted messages.

fun main() {
    val poem = """
        Roses are red,
        Kotlin is fun,
        Null safety saves you
        Before code is run.
    """.trimIndent()

    println(poem)
}

Common String Methods

• length: returns the number of characters
• uppercase() / lowercase(): change casing
• trim(): removes leading and trailing whitespace
• split(delimiter): breaks a string into a List<String>
• contains(text), startsWith(text), endsWith(text): search helpers returning Boolean
• replace(old, new): substitutes one substring for another

fun main() {
    val sentence = "  Kotlin is expressive and safe  "
    val cleaned = sentence.trim()

    println(cleaned.uppercase())
    println(cleaned.contains("safe"))
    println(cleaned.split(" "))
    println(cleaned.replace("safe", "concise"))
}