獲取時(shí)長：

  var audio = document.createElement('audio');
  audio.src = 'www.baidu.com';
  audio.addEventListener("canplay", function(){
      var sc=parseInt(document.getElementById('audio1').duration);
  });

獲取大小沒試過，依照樓上的試試看

這個(gè)一般是提供到請(qǐng)求頭的時(shí)候才能讀到的吧。像文件大小的話，一般是head取獲取對(duì)應(yīng)url的響應(yīng)頭。舉個(gè)例子，我們用head方法訪問maven的下載鏈接，可以得到下面的響應(yīng)頭：

HTTP/1.1 200 OK
ETag: "******************"
Content-Type: application/zip
Last-Modified: Sat, 24 Feb 2018 19:51:39 GMT
X-Checksum-MD5: **************************
X-Checksum-SHA1: ********************************
Via: 1.1 varnish
Accept-Ranges: bytes
Age: 2319984
Content-Length: 8958105
Accept-Ranges: bytes
Date: Tue, 03 Jul 2018 08:17:33 GMT
Via: 1.1 varnish
Connection: keep-alive
X-Served-By: cache-iad2145-IAD, cache-sea1046-SEA
X-Cache: HIT, HIT
X-Cache-Hits: 0, 0
X-Timer: S1530605854.978168,VS0,VE0

這里的Content-Length就是文件大小了