How can I get/extract the name value of a submit button? - php

Question

When I create i form - I do something like this:
<form name="form-name" method="post" action="?<?=$_SERVER['QUERY_STRING']?>">
[...some elements...]
<input type="submit" name="form-name" value="button">
</form>
Now I need to get the value of the name="" of the submit button, and not the actual value="".
In this case : "form-name".
And here's why:
When I submit a form; I write the action to database - and therefor need the name of the form submitted.
I know I can just have a hidden field with the form name. But I would like to make it simpler by just extracting the name from the submit button because I have a couple of other hidden form elements that I need to add on every single form I create to make my template system work.
And no javascript...

Answer 1

So, let's say your HTML form is this:
<form name="form-name" method="post" action="">
<input type="submit" name="form-name" value="button">
</form>
And you want to get what is inside name="form-name" in this case the form-name
Well, then in the PHP side you can, treat the $_POST global as associative array, and extract the key from it like this:
<?php
if(isset($_POST)){
foreach($_POST as $key=>$each){
echo $key; // this will output "form-name"
}
}

Answer 2

I might have come up with a solution to my question...
Here's a example form:
<form name="vehicle-vinNr" method="post" action="?<?=$_SERVER['QUERY_STRING']?>">
<input type="hidden" name="hello" value="world" readonly>
<input type="text" name="element">
<input type="submit" name="vehicle-vinNr" value="send">
</form>
First I need to extract and place the element-names into a new array:
<?php
if ($_POST){
foreach($_POST as $_FORM_ELEMENT_name => $_FORM_ELEMENT_value){
$_FORM_ELEMENT_names[] = $_FORM_ELEMENT_name;
}
}
?>
In this case the array now contains:
hello
element
vehicle-vinNr
If the submit-button is, and always is, the last element in the form - this would work:
$_FORM_name = end($_FORM_ELEMENT_names); // vehicle-vinNr
But sometimes the submit-button is not the last element, so I needed to make a change:
If I always start the name of the submit-button with submit_ - e.g. submit__vehicle-vinNr or with multiple submit buttons for different actions like submit_update__vehicle-vinNr/submit_delete_vehicle-vinNr I can just do this:
if ($_POST){
foreach($_POST as $_FORM_ELEMENT_name => $_FORM_ELEMENT_value){
if(strstr($_FORM_ELEMENT_name,'submit_')){
$_FORM_ELEMENT_submit_name = explode('__',$_FORM_ELEMENT_name);
$_FORM_name = $_FORM_ELEMENT_submit_name[1]; // vehicle-vinNr
}
}
}
This is the solution I came up with - any thoughts?