js 正则 获取文件名
获取文件名,不带后缀
var url = '124.333.444.txt.pdf.xlxs'
var reg = /\.\w+$/;
var fileName = url.replace(reg, '');
console.log('fileName', fileName); // 124.333.444.txt.pdf
获取文件后缀
var url = '124.333.444.txt.pdf.xlxs'
const FileExt = url.replace(/.+\./, ""); // xlxs
const fileExtension = url.substring(url.lastIndexOf('.') + 1); // xlxs