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
生成加密性强的伪随机数据。size参数是一个数字，表示要生成的字节数。
// Asynchronous
const {
randomBytes,
} = require('crypto');
randomBytes(256, (err, buf) => {
if (err) throw err;
console.log(`${buf.length} bytes of random data: unique random ID ${buf.toString('hex')}`);
});
知道更多
其他回答
更容易，没有额外的模块
Math.random().toString(26).slice(2)
安装NPM uuid包(来源:https://github.com/uuidjs/uuid):
npm install uuid
并在你的代码中使用它，例如ES6导入:
import { v4 as uuidv4, v6 as uuidv6 } from 'uuid';
uuidv4();
uuidv6();
或者使用CommonJS需要:
const {
v1: uuidv1,
v4: uuidv4,
} = require('uuid');
uuidv1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a'
uuidv4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1'
For
让count = 0; 令previous = 0; const generateUniqueId = () => { const time = new Date().getTime() Count = time > previous ?0:(++计数) Const uid =时间+计数 Previous = uid 返回uid ｝
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();
