How can i use $_POST if the name is a variable? - php

Question

I have a button that generates after each table row is generated in the loop, the name of each consecutive button is generated by $a++ variable. How do i use the $_POST method on my edit_contact.php page so i can use the variable from the $_POST array?
The variable is stored in the $_POST array, i have checked with Print_r($_POST); for example when i click on the third row edit button of the table, it will display as:
Array ( [3] => edit )
Here is the code of the loop on my list_contact.php page:
$a = "0";
// print whether success or not
if ($rst)
{
if (mysql_num_rows($rst)>0) // chech there are records
{
echo "<form name=addcontact method=post action=edit_contact.php>";
echo "<table border=\"1\" cellspacing=\"0\">";
/*** print out feild names ***/
while ($row = mysql_fetch_array($rst)) // fetch each row
{
echo "<tr>";
for ($i=0; $i<mysql_num_fields($rst); $i++) //for ech row print out field values
{
echo "<td>" . $row[$i] . "</td>";
}
echo "<td>" . "<input id=button type=submit name=" . $a++ . " value=Edit" . "</td>";
echo "</tr>";
}
echo "</table>";
echo "</form>";
}
else
{
echo "There are no records in the database";
}
}
And here is the code i am having trouble with on my edit_contact.php:
$qry = "SELECT * FROM contacts WHERE ContactID = " . $_POST;
How can i get that post to reflect just my variable? ie 3

Answer 1

You can do it once. You don't need any more fields. Just use foreach to access its key
foreach($_POST as $key => $value){
if(strtolower(trim($value)) == "edit"){ // Validate if editing being sent
// Display it if true
echo $key; // and this is the variable you want
}
}

Answer 2

you could use a hidden input field so instead of:
echo "<td>" . "<input id=button type=submit name=" . $a++ . " value=Edit" . "</td>";
you could do:
echo '<td><form method="post"><input type="hidden" name="ContactID" value="'.($a++).'"><input id="button" type="submit" value="Edit"></form></td>';
then retrieve the hidden input field like:
$ContactID = $_POST['ContactID'];
Note: You will still need to properly escape your POST data before using it for SQL queries, but hopefully this will point you in the right direction.

Answer 3

Restructure the code so that the name is actually a constant, and the value is dynamic.
echo "<td><input id=button type=submit name=\"edit\" value=\"" . $a++ . "\"></td>";
This way you can access it with:
$_POST['edit'];
And it will yield the value of: value=\"" . $a++ . "\" for the button that was clicked.
Which will return something like 3, as you desire.