我想要一个5个字符的字符串，由从集合[a-zA-Z0-9]中随机选取的字符组成。
用JavaScript实现这一点的最佳方法是什么？
当前回答
function generate(length) {
var letters = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z","A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z","0","1","2","3","4","5","6","7","8","9"];
var IDtext = "";
var i = 0;
while (i < length) {
var letterIndex = Math.floor(Math.random() * letters.length);
var letter = letters[letterIndex];
IDtext = IDtext + letter;
i++;
}
console.log(IDtext)
}
其他回答
最重要的是，所有的答案都是完美的。但我要补充的是，生成任何随机字符串值都非常好而且快速
函数randomStringGenerator（stringLength）{var randomString=“”；//选择变量的空值const allCharacters=“`~！@#$%^&*（）_+-={}[]：；\'<>？，./|\\ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijlmnopqrstuvwxyz0123456789'”；//所有字母数字字母列表while（stringLength--）{randomString+=allCharacters.substr（Math.floor（（Math.random（）*allCharacters.length）+1），1）；//使用Math.random（）从所有字符变量中选择任意值}return randomString；//返回生成的字母数字字符串}console.log（randomStringGenerator（10））//通过输入所需的随机字符串来调用函数
or
console.log（Date.now（））//它每次都会产生随机的十三个数字字符值。console.log（Date.now（）.toString（）.length）//打印生成字符串的长度
这是doubletap答案的稍微改进版本。当Math.random（）返回0、0.5、0.25、0.125等时，它会考虑gertas对案例的评论。
((Math.random()+3*Number.MIN_VALUE)/Math.PI).toString(36).slice(-5)
它防止零被传递给toString，我将最小的浮点值添加到Math.random（）。它确保传递给toString的数字有足够的数字，通过除以一个几乎不合理的数字。
随机unicode字符串
此方法将返回一个随机字符串，其中包含任何受支持的unicode字符，这不是OP要求的100%，而是我想要的：
function randomUnicodeString(length){
return Array.from({length: length}, ()=>{
return String.fromCharCode(Math.floor(Math.random() * (65536)))
}).join('')
}
根本原因
这是谷歌搜索“随机字符串javascript”时的最高结果，但OP只要求a-zA-Z0-9。
您可以使用base64：
function randomString(length)
{
var rtn = "";
do {
rtn += btoa("" + Math.floor(Math.random() * 100000)).substring(0, length);
}
while(rtn.length < length);
return rtn;
}
//创建一个长度为10的随机代码，您可以随意更改它
function createRandomCode(length) {
let randomCodes = '';
let characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
let charactersLength = characters.length;
for (let i = 0; i < length; i++ ) {
randomCodes += characters.charAt(Math.floor(Math.random() * charactersLength))
}
console.log("your reference code is: ".toLocaleUpperCase() + randomCodes);
};
createRandomCode(10)
