How can I remove a character from a string using Javascript?

user1293504 picture user1293504 · Mar 29, 2012 · Viewed 1M times · Source

I am so close to getting this, but it just isn't right. All I would like to do is remove the character r from a string. The problem is, there is more than one instance of r in the string. However, it is always the character at index 4 (so the 5th character).

example string: crt/r2002_2

What I want: crt/2002_2

This replace function removes both r

mystring.replace(/r/g, '')

Produces: ct/2002_2

I tried this function:

String.prototype.replaceAt = function (index, char) {
    return this.substr(0, index) + char + this.substr(index + char.length);
}
mystring.replaceAt(4, '')

It only works if I replace it with another character. It will not simply remove it.

Any thoughts?

Answer

JKirchartz picture JKirchartz · Mar 29, 2012
var mystring = "crt/r2002_2";
mystring = mystring.replace('/r','/');

will replace /r with / using String.prototype.replace.

Alternatively you could use regex with a global flag (as suggested by Erik Reppen & Sagar Gala, below) to replace all occurrences with

mystring = mystring.replace(/\/r/g, '/');

EDIT: Since everyone's having so much fun here and user1293504 doesn't seem to be coming back any time soon to answer clarifying questions, here's a method to remove the Nth character from a string:

String.prototype.removeCharAt = function (i) {
    var tmp = this.split(''); // convert to an array
    tmp.splice(i - 1 , 1); // remove 1 element from the array (adjusting for non-zero-indexed counts)
    return tmp.join(''); // reconstruct the string
}

console.log("crt/r2002_2".removeCharAt(4));

Since user1293504 used the normal count instead of a zero-indexed count, we've got to remove 1 from the index, if you wish to use this to replicate how charAt works do not subtract 1 from the index on the 3rd line and use tmp.splice(i, 1) instead.