Calling an array element created from a for loop - php

Question

I have an array that is created from a mysqli query.
The array then goes through a for loop to display a table.
Within the table there is a form submit that needs to take the selected row and pass the information into a variable to be modified.
I tried to take a screenshot, but I just joined and have no rep. In theory, the user needs to be able to select Modify and the array elements for that row need to pass into text input boxes with a preset value of $row[$j][0] where $j is fixed based on the row selected to modify.
Here is what this part of the code looks like.
if (isset($_POST['Select']) &&
isset($_POST['Search']))
{
$Select = get_post($con,'Select');
$Search = get_post($con,'Search');
if ($Select == "Invalid")
{
echo "<br /><br />Please select a search catagory";
}
else if ($Search == NULL)
echo "<br /><br />Please enter search field";
else
{
$query = "SELECT * FROM table WHERE $Select LIKE '$Search%'";
$result = mysqli_query($con,$query);
if (!mysqli_query($con,$query)) {
die('Error: ' . mysqli_error($con));
}
$rows = mysqli_num_rows($result);
echo "<table id='myTable' class='tablesorter'>
<thead><tr>
<th>Modify</th>
<th>Field1</th>
<th>Field2</th>
<th>etc...</th>
</tr></thead><tbody>";
for ($j = 0 ; $j < $rows ; ++$j)
{
$row = mysqli_fetch_row($result);
$modrow[$j] = $row;
echo <<<_END
<tr>
<td><form action="Lookup.php" method="post"><input type="submit" value="Modify" /><input type="hidden" name="submitted" value="$modrow[$j]"</form></td>
<td>$row[0]</td>
<td>$row[1]</td>
<td>etc...</td>
</tr><br />
_END;
}
echo "</tbody></table>";
if (isset($_POST['submitted']))
{
echo <<<_END
<form action="Lookup.php" method="post"><pre>
Field1 <input type="text" name="Field1" size="50" **value="$modrow[$j][0]"** />
...more of the same...

Answer 1

From what I gather, you're wanting to pass a request to the server containing some form of identifier for the row so that you may create a form for users to modify that row's data. Sorry if I misunderstood - I would ask first if I understood you correctly as a comment, but don't have enough rep.
You can use an id to submit to the server.
<button type="submit" name="modify" value="<?= $theRowsId ?>">Modify</button>
Think of the values of name and value attributes as a function/method and value being passed respectively.
Now when Modify is clicked, you can get retrieve the ID, perform a query for the ID and populate the input with the rows data.
$rowId = $_POST['modify'];