function generate(count) {
    var founded = false,
        _sym = 'abcdefghijklmnopqrstuvwxyz1234567890',
        str = '';
    while(!founded) {
        for(var i = 0; i < count; i++) {
            str += _sym[parseInt(Math.random() * (_sym.length))];
        }
        base.getID(string, function(err, res) {
            if(!res.length) {
                founded = true; // How to do it?
            }
        });
    }
    return str;
}

如何设置一个变量值与数据库查询回调?我该怎么做呢?


当前回答

更容易,没有额外的模块

Math.random().toString(26).slice(2)

其他回答

你可以使用urid包npm安装urid

import urid from 'urid';

urid(); // qRpky22nKJ4vkbFZ

阅读完整的文档:https://www.npmjs.com/package/urid

// Set the size
urid(8); //ZDJLC0Zq

// Use the character set
urid('num'); // 4629118294212196
urid('alpha'); // ebukmhyiagonmmbm
urid('alphanum'); // nh9glmi1ra83979b

// Use size with character set
urid(12, 'alpha'); // wwfkvpkevhbg

// use custom character set
urid(6, '0123456789ABCDEF'); // EC58F3
urid('0123456789ABCDEF'); // 6C11044E128FB44B

// some more samples
urid()               // t8BUFCUipSEU4Ink
urid(24)             // lHlr1pIzAUAOyn1soU8atLzJ
urid(8, 'num')       // 12509986
urid(8, 'alpha')     // ysapjylo
urid(8, 'alphanum')  // jxecf9ad

// example of all character sets
urid('num')          // 5722278852141945
urid('alpha')        // fzhjrnrkyxralgpl
urid('alphanum')     // l5o4kfnrhr2cj39w
urid('Alpha')        // iLFVgxzzUFqxzZmr
urid('ALPHA')        // ALGFUIJMZJILJCCI
urid('ALPHANUM')     // 8KZYKY6RJWZ89OWH
urid('hex')          // 330f726055e92c51
urid('HEX')          // B3679A52C69723B1

// custom character set
urid('ABCD-')        // ACA-B-DBADCD-DCA

在Node中创建随机32字符字符串的最快方法是使用本地crypto模块:

const crypto = require("crypto");

const id = crypto.randomBytes(16).toString("hex");

console.log(id); // => f9b327e70bbcf42494ccb28b2d98e00e

简单,基于时间,没有依赖:

(new Date()).getTime().toString(36)

or

Date.now().toString(36)

输出:jzlatihl


加上随机数(感谢@Yaroslav Gaponov的答案)

(new Date()).getTime().toString(36) + Math.random().toString(36).slice(2)

jzlavejjperpituute输出

我想用这个

class GUID { Generate() { const hex = "0123456789ABCDEF"; const model = "xxxxxxxx-xxxx-4xxx-xxxx-xxxxxxxxxxxx"; var str = ""; for (var i = 0; i < model.length; i++) { var rnd = Math.floor(Math.random() * hex.length); str += model[i] == "x" ? hex[rnd] : model[i] ; } return str.toLowerCase(); } } console.log(new GUID().Generate()); console.log(new GUID().Generate()); console.log(new GUID().Generate()); console.log(new GUID().Generate()); console.log(new GUID().Generate());

我正在使用以下,它是工作良好加上没有任何第三方依赖。

const {
  randomBytes
} = require('crypto');

const uid = Math.random().toString(36).slice(2) + randomBytes(8).toString('hex') + new Date().getTime();