在Scala中使用Circe将空值映射为None

libraryDependencies += "io.circe" %% "circe-core" % "0.14.1"
libraryDependencies += "io.circe" %% "circe-generic" % "0.14.1"
libraryDependencies += "io.circe" %% "circe-parser" % "0.14.1"

import io.circe._
import io.circe.parser._

case class MyData(name: Option[String], age: Option[Int])

object MyData {
  implicit val decodeMyData: Decoder[MyData] = (c: HCursor) =>
    for {
      name <- c.downField("name").as[Option[String]]
      age <- c.downField("age").as[Option[Int]]
    } yield MyData(name, age)
}

val jsonStr = """{"name": null, "age": 25}"""
val result = decode[MyData](jsonStr)

result match {
  case Right(data) => println(data)
  case Left(error) => println(s"Decoding failed: $error")
}