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
这是我的方法(使用TypeScript)。
我决定写另一个响应,因为我没有看到任何使用现代js和干净代码的简单解决方案。
const DEFAULT_ALPHABET = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
function getRandomCharFromAlphabet(alphabet: string): string {
return alphabet.charAt(Math.floor(Math.random() * alphabet.length));
}
function generateId(idDesiredLength: number, alphabet = DEFAULT_ALPHABET): string {
/**
* Create n-long array and map it to random chars from given alphabet.
* Then join individual chars as string
*/
return Array.from({length: idDesiredLength}).map(() => {
return getRandomCharFromAlphabet(alphabet);
}).join('');
}
generateId(5); // jNVv7
其他回答
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)
}
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('')
这不是一个完美的解决方案,但它应该奏效。如果出现任何错误,请增加Uint8Array()构造函数中给定的值。此方法的优点是它使用getRandomValues()方法生成加密的强随机值。
var array=新Uint8Array(20);crypto.getRandomValues(数组);var arrayEncoded=btoa(String.fromCharCode(…array)).split(“”);var arrayFiltered=arrayEncoded.filter(值=>{开关(值){大小写“+”:return false;大小写“/”:return false;case“=”:return false;违约:返回true;}});var password=arrayFiltered.slice(0,5).join('');console.log(密码);
紧凑型
var array=新Uint8Array(20);crypto.getRandomValues(数组);var password=btoa(String.fromCharCode(…array)).split(“”).filter(值=>{回来['+','/','=']includes(value);}).切片(0,5).连接('');console.log(密码);
//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)
从字符a-Za-z0-9中随机化字符串的另一种好方法:
function randomString(length) {
if ( length <= 0 ) return "";
var getChunk = function(){
var i, //index iterator
rand = Math.random()*10e16, //execute random once
bin = rand.toString(2).substr(2,10), //random binary sequence
lcase = (rand.toString(36)+"0000000000").substr(0,10), //lower case random string
ucase = lcase.toUpperCase(), //upper case random string
a = [lcase,ucase], //position them in an array in index 0 and 1
str = ""; //the chunk string
b = rand.toString(2).substr(2,10);
for ( i=0; i<10; i++ )
str += a[bin[i]][i]; //gets the next character, depends on the bit in the same position as the character - that way it will decide what case to put next
return str;
},
str = ""; //the result string
while ( str.length < length )
str += getChunk();
str = str.substr(0,length);
return str;
}