如何在除字符串中的最后一项之外的所有内容中添加逗号

Question

How do i add a comma after each row except for the last row.

while ($row = mysqli_fetch_array($result))
{
echo $row['categoryID']." ";
}

Currently displaying Action Adventure Drama I want it to display like this Action, Adventure, Drama

If i just echo the comma it will display like Action, Adventure, Drama,

Answer 1

You need to simply take an array of categories.

And convert it into a string by implode() .

This is the simplest solution we can have.

<?php
$categories = array();
while ($row = mysqli_fetch_array($result)) {
 $categories[] = $row['categoryID'];
}
echo implode(', ' , $categories);
?>

If you use string function, you need to append new category ids every time in the loop along with comma.

And then remove comma from right part of string using rtrim() .

Instead of this implode() works in one go.

Answer 2

TRY rtrim() to remove last comma from string

Using string :- use rtrim() to cut last comma from string

$str='';
while ($row = mysqli_fetch_array($result)) {
  $str .= $row['categoryID'].", ";
}
$str = rtrim($str,',');

Using array :- use implode() to convert array in string with glue(comma)

$str = array();
while ($row = mysqli_fetch_array($result)) {
  $str[] = $row['categoryID'].", ";
}
$newstr = implode(', ' , $str);