I want a solution in JavaScript to replace Alternative characters in a string with a " * ".
we have a string with X chars
mask every alternative N chars in the String
I am able to mask every alternative char with "*"
let str = "abcdefghijklmnopqrstuvwxyz"
for(let i =0; i<str.length; i =2){
str = str.substring(0, i) '*' str.substring(i 1);
}
console.log(str)
Output: > "*b*d*f*h*j*l*n*p*r*t*v*x*z"
Not sure how to mask the N values
Example:
let string = "9876543210"
N = 1; Output: 9*7*5*3*1*
N = 2; Output: 98**54**10
N = 3; Output: 987***321*
What is the best way to achieve this (NOO REGEX)
CodePudding user response:
You could use Array.from
to map each character to either "*" or the unchanged character, depending on the index. If the integer division of the index by n
is odd, it should be "*". Finally turn that array back to string with join
:
function mask(s, n) {
return Array.from(s, (ch, i) => Math.floor(i / n) % 2 ? "*" : ch).join("");
}
let string = "9876543210";
console.log(mask(string, 1));
console.log(mask(string, 2));
console.log(mask(string, 3));
CodePudding user response:
This code should work:
function stars(str, n = 1) {
const parts = str.split('')
let num = n
let printStars = false
return parts.map((letter) => {
if (num > 0 && !printStars) {
num -= 1
return letter
}
printStars = true
num = 1
if (num === n) {
printStars = false
}
return '*'
}).join('')
}
console.log(stars('14124123123'), 1)
console.log(stars('14124123123', 2), 2)
console.log(stars('14124123123', 3), 3)
console.log(stars('14124123123', 5), 5)
console.log(stars(''))
Cheers
CodePudding user response:
This requires you to use the current mask as an argument and build your code upon it.
I also edited the function to allow other characters than the "*"
const number = 'abcdefghijklmnopqrstuvwxyzzz';
for(let mask = 1; mask <= 9; mask ){
console.log("Current mask:", mask, " Value: ",applyMask(number, mask));
}
function applyMask(data, mask, defaultMask = '*'){
// start i with the value of mask as we allow the first "n" characters to appear
let i;
let str = data;
for(i = mask; i < data.length ; i =mask*2){
// I used the same substring method you used the diff is that i used the mask to get the next shown values
// HERE
str = str.substring(0, i) defaultMask.repeat(mask) str.substring(i mask);
}
// this is to trim the string if any extra "defaultMask" were found
// this is to handle the not full size of the mask input at the end of the string
return str.slice(0, data.length)
}