JS 代码 "自增和自减" 小练习

2019-10-24  本文已影响0人  BJ000


<!DOCTYPE html>

<html lang="en">

<head>

      <meta charset="UTF-8">

      <title>自增和自减的练习</title>

     <script type="text/javascript">

                var n1=10;

                var n2=20;

                var n =n1++;      //n=10 n1=10+1  //  先赋值后自增

                console.log('n=' +n );     //10

                console.log('n1=' +n1);  //11

                n = ++n1;   //n=12 n2=12  //  先自增后赋值

               console.log('n=' +n);    //12

               console.log('n1=' +n1);   //12

               n =n2--;   //n=20  n2=20-1=19  // 先赋值后自减

               console.log('n=' +n);  //20

               console.log('n2=' +n2);  //19

               n = --n2;//n=18  n2=18  //  先自减后赋值

               console.log('n=' +n);  //18

               console.log('n2=' +n2);  //18

        </script>

</head>

<body>

</body>

</html>

上一篇 下一篇

猜你喜欢

热点阅读