how can i remove chars between indexes in a javascript string

Question

i have the following:

var S=\"hi how are you\";
var bindex = 2;
var eindex = 6;

how can i remove all the chars from S that reside between

Answer 1

try

S = S.substring(0, bindex)+S.substring(eindex);

Answer 2

A solution that doesn't require creating any intermediate arrays or strings is to use .replace to capture the first characters in a group, match the characters you want to remove, and replace with the first captured group:

// keep first 3 characters, remove next 4 characters
const s = "hi how are you";
console.log(
  s.replace(/(.{3}).{4}/, '$1')
);

Answer 3

DON'T USE SLICE; TRY SPLICE

While slice is good and all, it was designed like substring, it was designed to get stuff, not remove stuff.

Caveat: splice was written for Arrays.

Good news: strings are easily turned into Arrays.

String.prototype.splice = function(start, deleteCount) {
  const newStringArray = this.split('')
  newStringArray.splice(start, deleteCount)
  return newStringArray.join('')
}

'Hello World'.splice(2, 5)
// Output -> "Heorld"

Answer 4

Want to delete multiple ranges in a string at once? It can be tricky because indexes will change as you cut out pieces of a string, but here's something quick that might work depending on your requirements:

function deleteRangesInString(ranges, string, deleteChar = "▮") {
    ranges.forEach(r => {
        string = string.substring(0, r[0]) + deleteChar.repeat((r[1]-r[0])+1) + string.substring(r[1]+1);
    })
    return string.replace(new RegExp(deleteChar, 'g'), '');
}

var s = 'hi how are you, look at me now, look at me now';

console.log(
deleteRangesInString([[2,9],[14,29]], s)
);