检查play.api.libs.json.Json中是否存在密钥

Question

contains类似于play.api.libs.json.Json

的功能

val data=Map("id" -> "240190", "password" -> "password","email" -> "email@domain.com")

data.contains("email")//true


val info=Json.obj("id" -> "240190", "password" -> "password","email" -> "email@domain.com")

现在如何检查info是否包含email？

Answer 1

info.keys.contains("email")

.keys会为您提供一个包含键值的Set，然后您可以调用contains方法，我不确定是否有更直接的方法这样做。

Answer 2

(info \ "email").asOpt[String].isEmpty

asOpt将返回Optional，我们可以进行isEmpty简单检查，这样做就可以了。

Answer 3

(info \ "email").asOpt[String] match {
  case Some(data) => println("here is the value for the key email represented by variable data" + data)
  case None => println("email key is not found") 
}