1 const randomStringMake = (count)=> {
2    const letter = "0123456789ABCDEFGHIJabcdefghijklmnopqrstuvwxyzKLMNOPQRSTUVWXYZ0123456789abcdefghiABCDEFGHIJKLMNOPQRST0123456789jklmnopqrstuvwxyz";
3    let randomString = "";
4    for (let i = 0; i < count; i++) {
5        const randomStringNumber = Math.floor(1 + Math.random() * (letter.length - 1));
6        randomString += letter.substring(randomStringNumber, randomStringNumber + 1);
7    }
8    return randomString
9}
10 
11console.log(randomStringMake(10))

1const alpha = 'abcdefghijklmnopqrstuvwxyz';
2const calpha = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
3const num = '1234567890';
4const specials = ',.!@#$%^&*';
5const options = [alpha, alpha, alpha, calpha, calpha, num, num, specials];
6let opt, choose;
7let pass = "";
8for ( let i = 0; i < 8; i++ ) {
9  opt = Math.floor(Math.random() * options.length);
10  choose = Math.floor(Math.random() * (options[opt].length));
11  pass = pass + options[opt][choose];
12  options.splice(opt, 1);
13}
14console.log(pass);
15

1function generatePassword(passwordLength) {
2  var numberChars = "0123456789";
3  var upperChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
4  var lowerChars = "abcdefghijklmnopqrstuvwxyz";
5  var allChars = numberChars + upperChars + lowerChars;
6  var randPasswordArray = Array(passwordLength);
7  randPasswordArray[0] = numberChars;
8  randPasswordArray[1] = upperChars;
9  randPasswordArray[2] = lowerChars;
10  randPasswordArray = randPasswordArray.fill(allChars, 3);
11  return shuffleArray(randPasswordArray.map(function(x) { return x[Math.floor(Math.random() * x.length)] })).join('');
12}
13
14function shuffleArray(array) {
15  for (var i = array.length - 1; i > 0; i--) {
16    var j = Math.floor(Math.random() * (i + 1));
17    var temp = array[i];
18    array[i] = array[j];
19    array[j] = temp;
20  }
21  return array;
22}
23
24alert(generatePassword(12));