If an HTML form has two <input type="submit"> buttons, how do I know which got clicked?
Suppose I have the following HTML form:
<form>
...
<input type="submit" name="queue" value="Queue item">
<input type="submit" name="submit" value="Submit item">
</form>
How do I know which button the user clicked (without using javascript)?
I looked at submitted data and it seems that when "Queue Item" is clicked then "queue" = "Queue Item" gets sent to the server. And when "Submit item" is clicked then "submit" = "Submit item" sets sent.
Can I rely on this behavior? Is it documented somewhere in the standard on HTML forms? How do you guys do it?
Answer
Yes, you can rely on this; it's fully documented here. The specific relevant lines say:
When a form is submitted for processing, some controls have their name paired with their current value and these pairs are submitted with the form. Those controls for which name/value pairs are submitted are called successful controls.
and
If a form contains more than one submit button, only the activated submit button is successful.