2019年5月20日 星期一

Kotlin學習筆記(11) Null Safety

Kotlin學習筆記(11)  Null Safety


fun main() {
var b: String? = "abc"
b = null // ok
println(b)
   
    val c: String? = "Kotlin"
if (c != null && c.length > 0) {
    println("String of length ${c.length}")
} else {
    println("Empty string")
}
   
    val e: String? = ""
if (e != null && e.length > 0) {
    println("String of length ${e.length}")
} else {
    println("Empty string")
}

}
null String of length 6 Empty string

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