简介
UUID(Universally Unique IDentifier) 全局唯一标识符。
UUID是一种由算法生成的二进制长度为128位的数字标识符。UUID的格式为“xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx”，其中的 x 是 0-9 或 a-f
范围内的一个32位十六进制数。在理想情况下，任何计算机和计算机集群都不会生成两个相同的UUID。
1.第一种
function guid() {
return '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);
});
}
guid() // "a1ca0f7b-51bd-4bf3-a5d5-6a74f6adc1c7"2.第二种
function uuid() {
var s = [];
var hexDigits = "0123456789abcdef";
for (var i = 0; i < 36; i++) {
s[i] = hexDigits.substr(Math.floor(Math.random() * 0x10), 1);
}
s[14] = "4"; // bits 12-15 of the time_hi_and_version field to 0010
s[19] = hexDigits.substr((s[19] & 0x3) | 0x8, 1); // bits 6-7 of the clock_seq_hi_and_reserved to 01
s[8] = s[13] = s[18] = s[23] = "-";
var uuid = s.join("");
return uuid;
}
uuid() // "ffb7cefd-02cb-4853-8238-c0292cf988d5"3.第三种
function guid2() {
function S4() {
return (((1 + Math.random()) * 0x10000) | 0).toString(16).substring(1);
}
return (S4() + S4() + "-" + S4() + "-" + S4() + "-" + S4() + "-" + S4() + S4() + S4());
}
guid2() // "748eea29-f842-4af9-a552-e1e1aa3ed979"4.第四种
// 指定长度和基数
function uuid2(len, radix) {
var chars = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'.split('');
var uuid = [],
i;
radix = radix || chars.length;
if (len) {
// Compact form
for (i = 0; i < len; i++) uuid[i] = chars[0 | Math.random() * radix];
} else {
// rfc4122, version 4 form
var r;
// rfc4122 requires these characters
uuid[8] = uuid[13] = uuid[18] = uuid[23] = '-';
uuid[14] = '4';
// Fill in random data. At i==19 set the high bits of clock sequence as
// per rfc4122, sec. 4.1.5
for (i = 0; i < 36; i++) {
if (!uuid[i]) {
r = 0 | Math.random() * 16;
uuid[i] = chars[(i == 19) ? (r & 0x3) | 0x8 : r];
}
}
}
return uuid.join('');
}
uuid2(16, 16) // "277571702EE33E11"5.第五种
说明:生成32位UUID方法
function uuid() {
var s = [];
var hexDigits = "0123456789abcdef";
for (var i = 0; i < 32; i++) {
s[i] = hexDigits.substr(Math.floor(Math.random() * 0x10), 1);
}
s[14] = "4"; // bits 12-15 of the time_hi_and_version field to 0010
s[19] = hexDigits.substr((s[19] & 0x3) | 0x8, 1); // bits 6-7 of the clock_seq_hi_and_reserved to 01
s[8] = s[13] = s[18] = s[23];
var uuid = s.join("");
return uuid;
}到此这篇关于JavaScript生成UUID的五种方法详解的文章就介绍到这了,更多相关JavaScript生成UUID内容请搜索编程网以前的文章或继续浏览下面的相关文章希望大家以后多多支持编程网！
