How do I get rid if the last character of a string javascript?
Question
I do not understand why I cannot remove the last character in my string. Here is my javascript code.
<!DOCTYPE html>
<html>
<body>
<p id="demo"></p>
<script>
function array2ArrayOfStrings(arr) {
var lines = [new Array()];
var l = 0;
lines[0].push(arr[0] + ', ');
for(i=1; i < arr.length; i++) {
lines[l] += arr[i] + ', ';
if(lines[l].length > 20) {
lines.push(new Array());
l++;
}
}
console.log('last is ' + lines[l]);
// var newStr = str.substring(0, str.length - 1);
lines[l] = lines[l].substring(0, lines[l].length - 1);
// lines[l] = lines[l].slice(0,-1);
return lines.join('<br>');
}
var cars = [
'CRX',
'Mustang',
'Volvo XXX',
'Toyota Pickup',
'Volkswagon Beatle',
'Datsun',
'Lincoln',
'Cadillac',
'Mercedes',
'Lexus',
];
document.getElementById("demo").innerHTML = array2ArrayOfStrings(cars);
</script>
</body>
</html>
Here's a link where you can run the above: https://www.w3schools.com/code/tryit.asp?filename=G6MDZQFMAK4K
The output I get is this:
CRX, Mustang, Volvo XXX,
Toyota Pickup, Volkswagon Beatle,
Datsun, Lincoln, Cadillac,
Mercedes, Lexus,
I want to get rid of that last , after Lexus .
2 answers
solution1
2 ACCPTED 2019-08-03 04:59:43
Try
lines[l].substring(0, lines[l].length - 2);
because you are adding ,SPACE (two characters)
<p id="demo"></p> <script> function array2ArrayOfStrings(arr) { var lines = [new Array()]; var l = 0; lines[0].push(arr[0] + ', '); for (i = 1; i < arr.length; i++) { lines[l] += arr[i] + ', '; if (lines[l].length > 20) { lines.push(new Array()); l++; } } lines[l] = lines[l].substring(0, lines[l].length - 2); console.log('last is ' + lines[l]); return lines.join('<br>'); } var cars = [ 'CRX', 'Mustang', 'Volvo XXX', 'Toyota Pickup', 'Volkswagon Beatle', 'Datsun', 'Lincoln', 'Cadillac', 'Mercedes', 'Lexus', ]; document.getElementById("demo").innerHTML = array2ArrayOfStrings(cars); </script>
solution2
2 2019-08-03 04:59:46
Your code actually is removing the last character in your string. At the moment the last character is a space as you are appending , to your last element, so, when you do lines[l] = lines[l].substring(0, lines[l].length - 1); you're removing the space, and not the the comma , . To remove both the space and comma, you need to change your -1 to a -2 like so:
lines[l] = lines[l].substring(0, lines[l].length - 2);
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