Google Sheet custom function not returning string - string

Question

I am new to Google Sheet scripting.
I am writing a code to strip the sixth components from a long text that is based on a naming convention. The text have 6 parts all separated by an underscore. However, my code is not returning anything
function RetailerStrip(account) {
var count = 0;
var retname = "";
var retcount = 0;
for(var i = 0, len = account.length; i < len; i++) {
if (account[i] =="_") {
++count;
}
if (count == 5) {
retname[retcount]= account[i];
++retcount;
}
}
return retname;
}
I then call this function from sheet as below
=RetailerStrip("abc_def_ghi_jkl_mno_pqr")
When I tried to declare 'retname' as an array the function did return the required text (fifth component) but the text was spread across multiple cells with on character in each cell, and not as a single string in one cell
var retname = [];
Please help

Answer 1

You could try this:
function RetailerStrip(str) { return str.split('_')[5]; }
The split() method creates an array.
But if you prefer to stick with the string-iteration method, you could use this:
function RetailerStrip(account) {
var count = 0;
var retname = []; // Array
var retcount = 0;
for (var i = 0, len = account.length; i < len; i++) {
if (account[i] =="_") {
++count;
}
if (count == 4) {
retname[retcount]= account[i];
++retcount;
}
}
retname.shift(); // To get rid of the underscore from the array
var retnameString = retname.join(''); // To convert the array to a string
return retnameString;
}