console.log( ‘xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx‘.replace(/[xy]/g, function (c) {
var r = Math.random() * 16 | 0, v = c === ‘x‘ ? r : (r & 0x3 | 0x8);
return v.toString(16);
}))
思路：十六进制运算符转二进制，二进制转字符串。
原文：https://www.cnblogs.com/comsher/p/15221582.html