mySQL form input, insert by looping, not inserting - php

Question

I am new to StackOverflow, and relatively new to PHP. I have a mixture of a mySQL table and form input, where a user will enter numbers into a field (options) next to each corresponding record (companyid), then submit and these should be inserted into the mySQL table. If no "options" are entered, the loop should skip and move on.
When I submit, nothing is actually inserted into the database. I need a little help because I have looked at several examples and I thought I had everything correct.
Thank you so much!!
Below is the table with form inputs:
<?php
$result = mysqli_query($connection,"SELECT * FROM company_main");
echo "<form action='userinvestdynamic.php' method='post'>";
while($row = mysqli_fetch_array($result))
{
echo "<table border=1>";
echo "<tr>";
echo "<td>Company ID</td>";
echo "<td>" .$row['company_id'] . "</td>";
echo "<input type=hidden name=companyid[] value=" . $row['company_id'] . " />";
echo "<td><input type=number name=options[]></td>";
echo "</tr>";
echo "</table>";
}
echo "<input name='userinvestoptionsdynamic' type='submit' value='Invest!'>";
echo "</form>";
?>
And here is the code once the form is submitted.
<?php
require ('db_login.php');
session_start();
if (isset($_POST['userinvestoptionsdynamic'])) {
$userid = $_SESSION['login_user'];
$companyid = $_POST['companyid'];
$options = $_POST['options'];
// loop through array
$number = count($_POST['companyid']);
for ($i=0; $i<$number; $i++)
{
//store single company and options in local variables
$companyid = $companyid[$i];
$options = $options[$i];
//run insert for any items that don't have blank options
if($options[$i] <>''){
$query = "INSERT INTO user_company_invested(user_id, company_id, user_company_options_invested) VALUES($userid,$companyid,$options)";
mysqli_query($connection, $query);
}
}
header('Location: userpage.php');
} else {
echo 'error';
}
?>

Answer 1

Explanations are inside the comment /* */
<?php
$result = mysqli_query($connection,"SELECT * FROM company_main");
$counter=0; /* DECLARE THIS BEFORE YOUR WHILE LOOP */
echo "<form action='userinvestdynamic.php' method='post'>";
while($row = mysqli_fetch_array($result))
{
echo "<table border=1>";
echo "<tr>";
echo "<td>Company ID</td>";
echo "<td>" .$row['company_id'] . "</td>";
echo "<input type=hidden name=companyid[$counter] value=" . $row['company_id'] . " />"; /* DECLARE THE COUNTER ON COMPANY ID ARRAY */
echo "<td><input type=number name=options[$counter]></td>"; /* DECLARE THE COUNTER ON OPTIONS ARRAY */
echo "</tr>";
echo "</table>";
$counter=$counter+1; /* ADD 1 EVERY LOOP ON COUNTER */
}
echo "<input type='hidden' name='hiddencounter' value='$counter'>"; /* COUNT ALL THE LOOP AND SUBMIT IT TO THE NEXT FORM */
echo "<input name='userinvestoptionsdynamic' type='submit' value='Invest!'>";
echo "</form>";
?>
userinvestdynamic.php:
<?php
require ('db_login.php');
session_start();
if (isset($_POST['userinvestoptionsdynamic'])) {
$userid = $_SESSION['login_user']; /* I ASSUME YOU HAVE LOGIN_USER SESSION DECLARED IN THE PREVIOUS FILE? */
$companyid = $_POST['companyid'];
$options = $_POST['options'];
$counter = $_POST['hiddencounter']; /* THIS WILL SET AS YOUR COUNTER */
for ($i=0; $i<=$counter; $i++)
{
if(empty($options[$i])){ /* IF NO INPUT ON OPTIONS */
/* DO NOTHING */
}
else {
/* store single company and options in local variables */
$query = "INSERT INTO user_company_invested(user_id, company_id, user_company_options_invested)
VALUES($userid,$companyid[$i],$options[$i])";
mysqli_query($connection, $query);
} /* END OF ELSE IF NOT EMPTY COMPANY ID */
} /* END OF FOR LOOP */
header('Location: userpage.php');
} /* END OF ISSET USERINVESTOPTIONSDYNAMIC */
else {
echo 'Error!';
}
?>