js 字符串截取？

Question

这是一个录音链接，怎么能截取到6922，但是字符串有可能长短不同，而且数字位数也不一定，这怎么截取

/usr/files/20180523/a33e1377-7d70-4213-b59f-…4d51b1e673c5aef0eaf9d18472d.durationTime=6922.mp3

Answer 1

能保证是数字.mp3即可
正则

/(\d+)\.mp3$/

Answer 2

str.match(/(\\d+).mp3$/)[1]

Answer 3

const src = "/usr/files/20180523/a33e1377-7d70-4213-b59f4d51b1e673c5aef0eaf9d18472d.durationTime=6922.mp3"
const r = src.substring(src.indexOf('durationTime=')+'durationTime='.length, src.indexOf('.mp3'))

Answer 4

"/usr/files/20180523/a33e1377-7d70-4213-b59f-…4d51b1e673c5aef0eaf9d18472d.durationTime=6922.mp3".split("=")[1].split(".")[0];

Answer 5

var str = "4d51b1e673c5aef0eaf9d18472d.durationTime=6922.mp3";
    var substr = str.match(/durationTime=(\S*).mp3/);
    console.log(substr[1]);

Answer 6

str.match(/\d+(?=\.mp3\b)/ig);