scala-模式匹配

class A
case class A1(name:String,age:Int) extends A
case class A2(name:String,address:String) extends A

def  classMatch(c:A){
 c match {
  case A1(name,age) => println("类型是A1")
  case A2(name,address) => println("类型是A2")
  case _ => println("类型未知")
 }
}

def  listMatch(list:Any)={
 list match {
  case e1::e2::Nil => println("list仅有2个元素:"+e1+e2)
  case "abc"::"678"::"mmm"::Nil => println("list仅仅包含3个固定元素")
  case 0::tail => println("list以0开头包含"+(list.asInstanceOf[List[Int]]).length+"个元素")
  case 0::Nil => println("这个list仅仅包含0")
  case _ => println("没有匹配")
 }
}

def  arrayMatch(arr:Any)={
 arr match {
  case Array("abc") => println("only one abc")
  case Array("abc",1) => println("两个元素：abc和1")
  case Array(a,b) => println("两个动态元素:"+a+"-"+b)
  case Array(0,_*) => println("这个array以0开头元素个数不计:"+arr)
  case _ => println("没有匹配")
 }
}

//传入的参数，但判断类型时实际使用的是isInstanceOf[xxx]
def getNum(item:Any)={
 item match{
     case x:String => print("String")
     case i:Int => print("Int")
     case c:Char => print("Char")
     case _=>0//这个是完全没有匹配上的情况
 }
}

def testMatch(i:Int,s:String="default"):Unit={
 i match {
  case 1 => print("数字："+1)
  case 2 => print("数字："+2)
  case 3 => print("数字："+3)
  case 5 if(s equals "mz") => print("数字："+3+"mz")//匹配后仍可添加判断
  case tmp1 => print("tmp1的赋值数字："+tmp1)//会将i赋值给tmp1变量
  case _ => print("其它喽")
 }
}