PHP Form implode / explode - php

Question

I am using the a db field merchant_sku_item in a form. the original value is separated by / in the db like this:
2*CC689/1*CC368-8/1*SW6228-AB
I want to display in a text area on each line so I tried like this:
<textarea name="merchant_sku_item" rows="5" class="form-control" id="merchant_sku_item"><?
$items=explode('/',$merchant_sku_item);
foreach($items as $item){
echo $item."\r\n";
}
?></textarea>
All works fine:
2*CC689
1*CC368-8
1*SW6228-AB
but when I post the form I get a value like this:
2*CC689 1*CC368-8 1*SW6228-AB
but I wan't it back in the original format to update the DB in the correct format:
2*CC689/1*CC368-8/1*SW6228-AB
I tried to implode it with the / but I think it's just one string now so it's not working. I could replace the spaces I guess but this will not work if the field contains spaces.
Could somebody please tell me the best way to handle this?

Answer 1

The explode is correct, but you cannot just echo $item . "\r\n" because if $item contains </textarea> or whatever HTML you'll skrew up the page. You have to use echo htmlspecialchars($item) . "\n";. Normally, HTML pages have Linux line endings with "\n" and not Windows line endings with "\r\n".
To re-create the value for the DB, you have to take in consideration that the user may add some spaces or new lines. So you might not just get "\r\n" between the values but also " \n" or I don't know what. This is why a regular expression will be more flexible than a simple explode().
The regular expression pattern: \s+
The pattern \s will match any space, tab or new line chars. If you add the + sign after, it means that it can be 1 or multiple times. So this means that " \r\n" will match as it contains spaces, a carriege return and a new line. In PHP, you put the pattern between a delimiter char that you choose and that you put at the begin and the end. Commonly it's a slash so it becomes /\s+/. But you sometimes see also #\s+# or ~\s+~. After this delimiter, you can put some flags to change the way the regular expression is executed. Typically /hello/i will match "Hello" or "hello" because the i flag makes the search case-insensitive.
Similar to what you did: explode and re-implode example:
<?php
// Example of values that could be posted because users are always
// stupid and add spaces that they then don't see anymore.
$examples = [
"2*CC689 1*CC368-8 1*SW6228-AB", // spaces
"2*CC689\n1*CC368-8\n1*SW6228-AB", // new lines
"2*CC689\r\n1*CC368-8\r\n1*SW6228-AB", // carriege returns and new lines
"2*CC689\n 1*CC368-8 \n1*SW6228-AB", // new lines and spaces
];
foreach ($examples as $merchant_sku_item) {
$values = preg_split('/\s+/', $merchant_sku_item);
$merchant_sku_item_for_db = implode('/', $values);
echo $merchant_sku_item_for_db . "\n";
}
?>
Output:
2*CC689/1*CC368-8/1*SW6228-AB
2*CC689/1*CC368-8/1*SW6228-AB
2*CC689/1*CC368-8/1*SW6228-AB
2*CC689/1*CC368-8/1*SW6228-AB
Simplier, you could also just do a replacement with the same regular expression like this:
<?php
// Example of values that could be posted.
$examples = [
"2*CC689 1*CC368-8 1*SW6228-AB", // spaces
"2*CC689\n1*CC368-8\n1*SW6228-AB", // new lines
"2*CC689\r\n1*CC368-8\r\n1*SW6228-AB", // carriege returns and new lines
"2*CC689\n 1*CC368-8 \n1*SW6228-AB", // new lines and spaces
];
foreach ($examples as $merchant_sku_item) {
$merchant_sku_item_for_db = preg_replace('/\s+/', '/', $merchant_sku_item);
echo $merchant_sku_item_for_db . "\n";
}
?>
And just another important point regarding the data the user could input: What happens if the user types "2*CC/689" in the textarea?
Well, this will break your DB value :-/
This means that you have to validate the user input with some checks:
<?php
header('Content-Type: text/plain');
$examples = [
"2*CC689 1*CC368-8 1*SW6228-AB", // spaces
"2*CC689\n1*CC368-8\n1*SW6228-AB", // new lines
"2*CC689\r\n1*CC368-8\r\n1*SW6228-AB", // carriege returns and new lines
"2*CC689\n 1*CC368-8 \n1*SW6228-AB", // new lines and spaces
// Test with invalid datas:
"2*C/C689\n1*CC368-8\n1*SW6228-AB", // slash not allowed
"*CC689\n1*CC368-8\n1*SW6228-AB", // missing number before the *
"1*\n1*CC368-8\n1*SW62?28-AB", // missing product identifier and invalid ?
"1CC689 1*CC368-8 1SW6228-AB", // missing *
];
foreach ($examples as $example_nbr => $merchant_sku_item) {
echo str_repeat('=', 80) . "\n";
echo "Example $example_nbr\n\$merchant_sku_item = \"$merchant_sku_item\"\n";
$values = preg_split('/\s+/', $merchant_sku_item);
$errors = [];
foreach ($values as $i => $value) {
echo "Value $i = \"$value\"";
// Pattern: a number followed by * and followed by a product id (length between 3 and 10).
if (!preg_match('/^\d+\*[\d\w-]{3,10}$/i', $value)) {
echo " <-- ERROR\n";
$errors[] = $value;
} else {
echo "\n"; // It's ok
}
}
if (!empty($errors)) {
// You should handle the error and reload the form with the posted value and an error
// message explaining to the user what format is allowed.
echo "ERROR: Cannot save the value because the following products are wrong:\n";
echo implode("\n", $errors) . "\n";
}
}
?>
Test it here: https://onecompiler.com/php/3xtff6nk8

Answer 2

You can use preg_replace for your final post string like below code
$str = "2*CC689 blue 1*CC368-8 red 1*SW6228-AB";
$items = preg_replace('/\s+/', '/', $str);
echo $items;
output
2*CC689/blue/1*CC368-8/red/1*SW6228-AB
I Hope understand your question exactly.

Answer 3

Try replacing the created spaces and removing newline characters like so:
<?php
$merchant_sku_item = str_replace("\r\n","/",trim($_POST["merchant_sku_item"]));
?>

Answer 4

Make it this way:
<textarea name="merchant_sku_item" rows="5" class="form-control" id="merchant_sku_item"><?
$items=explode('//',$merchant_sku_item);
foreach($items as $item){
echo $item."\r\n";
}
?></textarea>