js 实现简易时钟效果

 1  <!-- 参考教程：https://www.cnblogs.com/carekee/articles/1678041.html -->
 2     <div id="time"></div>
 3     <script>
 4         time();
 5         setInterval(time,1000)
 6         function time() {
 7             var t = new Date();
 8             var y = t.getFullYear(),
 9                 m = t.getMonth() + 1,
10                 d = t.getDate(),
11                 h = t.getHours(),
12                 min = t.getMinutes(),
13                 s = t.getSeconds();
14                 if( y < 10 ){ y = '0' + y }
15                 if( d < 10 ){ d = '0' + d }
16                 if( h < 10 ){ h = '0' + h }
17                 if( min < 10 ){ min = '0' + min }
18                 if( s < 10 ){ s = '0' + s }
19             var full_time = y + '-' + m + '-' + d + ' ' + h + ':' + min + ':' + s;
20             document.getElementById('time').innerText = full_time;
21         }
22     </script>