I have string like below:
ABCDEFGH
And i want to reverse it like below:
GHEFCDAB
i have tried this:
var str = "ABCDEFGH";
var splitString = str.split("");
var reverseArray = splitString.reverse();
var joinArray = reverseArray.join("");
And return like below:
HGFEDCBA
I Know it wrong, and it just reverse it one way. how to reverse string in javascript with that condition? Many thank before.
You can do this, using regex :
let splited = str.match(/.{1,2}/g).reverse().join('');
str.match(/.{1,2}/g) to transform ABCDEFGH to [AB, CD, EF, GH]
reverse() to transform [AB, CD, EF, GH] to [GH, EF, CD, AB]
join('') to transform [GH, EF, CD, AB] to GHEFCDAB
Using empty String
const str = 'ABCDEFGH'
var emptyStr = '';
for(let i = str.length; i>1; i--){
emptyStr += str.slice(i-2,i)
i--
}
console.log(emptyStr);using empty Array
const str = 'ABCDEFGH'
const rev = str.split('');
const revStr = []
for(let i = str.length; i >=1; i--){
const strPair = rev.slice(i-2,i).join('');
i--;
revStr.push(strPair)
}
console.log(revStr.join(''))Output: GHEFCDAB
class RevStr{
constructor(input){
this.str =input;
}
reverseStr() {
let str = this.str.match(/.{1,2}/g)
let end = str.length-1;
let start = 0;
while (start < end) {
let temp = str[start];
str[start] = str[end];
str[end] = temp;
start++;
end--;
}
console.log(str.join(''));
}
}
let s = new RevStr("abcdefgh");
s.reverseStr();
Here are 3 simple solutions to reverse a string in JavaScript:
// Solution-1: Using reverse() method
function reverseString1(str) {
return str.split('').reverse().join('')
}
// Solution-2: Using for loop
function reverseString2(str) {
let reversed = '';
for(let character of str) {
reversed = character + reversed;
}
return reversed;
}
// Solution-3: Using reduce() method
function reverseString3(str) {
return str.split('').reduce((reversed, character) => character + reversed, '')
}
console.log("Solution 1: ", reverseString1("happy"));
console.log("Solution 2: ", reverseString2("database"));
console.log("Solution 3: ", reverseString3("loop")); 