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?
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
生成10个字符长的字符串。长度由参数设置(默认值为10)。
function random_string_generator(len) {
var len = len || 10;
var str = '';
var i = 0;
for(i=0; i<len; i++) {
switch(Math.floor(Math.random()*3+1)) {
case 1: // digit
str += (Math.floor(Math.random()*9)).toString();
break;
case 2: // small letter
str += String.fromCharCode(Math.floor(Math.random()*26) + 97); //'a'.charCodeAt(0));
break;
case 3: // big letter
str += String.fromCharCode(Math.floor(Math.random()*26) + 65); //'A'.charCodeAt(0));
break;
default:
break;
}
}
return str;
}
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)
}
这里有一些简单的一行。更改新阵列(5)以设置长度。
包括0-9a-z
new Array(5).join().replace(/(.|$)/g, function(){return ((Math.random()*36)|0).toString(36);})
包括0-9a-zA-Z
new Array(5).join().replace(/(.|$)/g, function(){return ((Math.random()*36)|0).toString(36)[Math.random()<.5?"toString":"toUpperCase"]();});
ES6编码(0-9a-z)
Array(5).fill().map(n=>(Math.random()*36|0).toString(36)).join('')
这个小巧的小把戏怎么样?
var possible = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
var stringLength = 5;
function pickRandom() {
return possible[Math.floor(Math.random() * possible.length)];
}
var randomString = Array.apply(null, Array(stringLength)).map(pickRandom).join('');
您需要Array.apply来将空数组变为未定义的数组。
如果您正在为ES2015进行编码,那么构建阵列会简单一些:
var randomString = Array.from({ length: stringLength }, pickRandom).join('');
这是Coffeescapet版本的一行代码
genRandomString = (length,set) -> [0...length].map( -> set.charAt Math.floor(Math.random() * set.length)).join('')
用法:
genRandomString 5, 'ABCDEFTGHIJKLMNOPQRSTUVWXYZ'
输出:
'FHOOV' # random string of length 5 in possible set A~Z