反斜线使用注意：

object A {
  def main(args: Array[String]): Unit = {
    val str = "\""
    val str1 = "\\\""
    println(str)
    println(str1)
    println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~")
    val a1 = "{\\\"userID\\\":\\\"1\\\",\\\"NewStepNum\\\":\\\"10001\\\"}"
    //    val a = "{\\"userID\\":\\"1\\",\\"NewStepNum\\":\\"10001\\"}"
    val a2 = "{\"userID\":\1 \",\"NewStepNum\":\"10001\"}"
    println(a1)
    println(a2)
  }
}

• 执行结果

"
\"
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
{\"userID\":\"1\",\"NewStepNum\":\"10001\"}
{"userID":\1 ","NewStepNum":"10001"}