POST values from multiple checkboxes to SQL - php

Question

I've got two tables in mySQL.
Table: Player
-----------------------------------------------------------
| name | T1 | T2 | T3 | T4 | T5 | id | weeknumber |
|--------|----|-----|-----|-----|-----|-----|-------------|
| | | | | | | | |
| | | | | | | | |
-----------------------------------------------------------
Table: Teams
-------------------------------------------------------------------------
| id | team1name | team2name | team1score | team2score | weeknumber |
|------|-----------|-----------|-------------|------------|-------------|
| | | | | | |
| | | | | | |
-------------------------------------------------------------------------
The idea is, that table "Teams" is getting populated through another page that already works for me.
Every week there will be 13 new teams.
Table "Player" has to get populated from another page where the user gets the following options:
Name: Text-field
13 Checkboxes (those checkboxes need to store the value ID from table Teams)
The user is supposed to check 5 out of 13 teams (free choice) and the values of those checkboxes (the ID of the Teams ID) should be stored as T1, T2, T3, T4, T5 along with Name from text-field.
<form method="post" action="created.php" class="form-style-7">
<h2>Tilmeld en spiller </h2>
<ul>
<li>
<label for="name">Navn</label>
<input type="text" name="navn" value="<?php echo $navn;?>">
<span>Indtast spillerens navn</span>
</li>
<li>
<?php
$count = $rows = 0;
$sql = "SELECT * FROM Teams WHERE weeknumber='$WeekNumber' ORDER BY id";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
echo '
<table class=""><tr><th colspan="3">Igangværende - Uge ' . $WeekNumber . '</th></tr>
<tr class="underhead"><td>#</td><td>Kamp</td><td>Mål</td></tr>
';
// Output af data
while($row = $result->fetch_assoc()) {
if ($rows % 1 == 0) {
$count++;
}
$rows++;
echo '<tr>';
echo '<td>';
echo '';
echo '<input type="hidden" name="ID" value="' . $row['id'] . '" >';
echo '<input class="btn" type="checkbox" name="" > ';
echo ' </form>';
echo '</td>';
echo '<td>' . $count . '</td>';
echo '<td>' . $row["team1name"]. ' - ' . $row["team2name"] . '</td>
</form>';
}
echo '</table>';
}
mysqli_close($conn);
?>
</li>
<li id="buttontilmeld">
<input type="submit" name="submit" value="Tilmeld" >
</li>
</ul>
</form>
Edit:
My created.php contains the following:
if (isset($_POST['navn']) && $_POST['navn'] != "") {
if (isset($_POST['navn'])) {
if ($_POST['name'] == "" || $_POST['T1'] == "" || $_POST['T2'] == "" || $_POST['T3'] == "" || $_POST['T4'] == "" || $_POST['T5'] == "") {
echo 'XX';
}
} else {
require 'config.php';
$conn = Connect();
$name = $conn->real_escape_string($_POST['navn']);
$match1 = $conn->real_escape_string($_POST['kamp1']);
$match2 = $conn->real_escape_string($_POST['kamp2']);
$match3 = $conn->real_escape_string($_POST['kamp3']);
$match4 = $conn->real_escape_string($_POST['kamp4']);
$match5 = $conn->real_escape_string($_POST['kamp5']);
$WeekNumber = date('W');
$query = "INSERT into Spillere (navn,kamp1,kamp2,kamp3,kamp4,kamp5,ugenummer) VALUES('" . $name . "','" . $match1 . "','" . $match2 . "','" . $match3 . "','" . $match4 . "','" . $match5 . "','" . $WeekNumber . "')";
$success = $conn->query($query);
if (!$success) {
die("Couldn't enter data: ".$conn->error);
echo "Thanks";
}
}
}
Where I need $_POST['TX']=="" to populate table Player T1 to T5.

Answer 1

The name attribute of the checkboxes are not set. PHP can't get any info about the checked checkboxes (unless you should use Jquery en do some other stuff). It's important to know that only checked checkboxes will be visible in the POST data.
Give your checkboxes a name, for example:
echo '<input class="btn" type="checkbox" name="team_checkbox_'.$row['id'].'"> ';
Then in the script created.php were your data is posted to you can catch these values by running the same SQL-query and trying
if(isset($_POST['team_checkbox_'.$row['id']])){
// $row['id'] is checked
}
Or just check all POST data:
$t = array();
foreach($_POST as $post_param_name => $value){
if(substr($post_param_name, 0, 14) == 'team_checkbox_'){
// substr($post_param_name, 14) is the ID of one of the checked groups
$t[] = substr($post_param_name, 14);
}
}
Now $t is an array containing the team ID's of the checkboxes. So you can save in your SQL: T1 = $t[1], ...

Answer 2

This answer should be reviewed, but the solution is in another answer here:
https://stackoverflow.com/a/47162431/1589379
Follow good coding standards
There's a lot of little problems with the code you posted. Ultimately, you should always be very careful to keep everything properly indented, and always use brackets {}, even if they're not needed.
Your original code:
while (...) {
if ($rows % 1 == 0)
$count++;
Should be:
while (...) {
if ($rows % 1 == 0) {
$count++;
}
Those adjustments would have made it much more clear that your code had two closing </form> tags, and no opening tags, within your while loop.