正则
group
const width1 = '100%';
const width2 = '20px';
const width3 = 719;
console.log(/(?<width>\d+)(?<unit>px|%)$?/.match(width1));
const width1 = '100%';
const width2 = '20px';
const width3 = 719;
console.log(/(?<width>\d+)(?<unit>px|%)$?/.match(width1));