util-helpers/lib/randomString.js

一个基于业务场景的工具方法库

'use strict';

var ut2 = require('ut2');

var letter = 'abcdefghijklmnopqrstuvwxyz';
var chars = {
    number: '0123456789',
    lower: letter,
    upper: letter.toUpperCase()
};
var allChars = chars.number + chars.lower + chars.upper;
function internalRandomString(len, pool, prefix) {
    if (prefix === void 0) { prefix = ''; }
    while (len-- > 0) {
        var r = pool[ut2.randomInt(0, pool.length - 1)];
        return internalRandomString(len, pool, prefix + r);
    }
    return prefix;
}
var randomString = function (len, pool) {
    if (len === void 0) { len = 0; }
    var _pool;
    if (typeof pool !== 'string') {
        _pool = allChars;
    }
    else if (chars[pool]) {
        _pool = chars[pool];
    }
    else {
        _pool = pool;
    }
    return internalRandomString(ut2.toNumber(len), _pool);
};

module.exports = randomString;