CODEWITHSUNDEEP
phphtml
Brodie
Brodie

Reputation: 8717

Difference between '#' and $_SERVER['PHP_SELF']

Just a general question. In terms of form actions if the form is submitting to it's parent page I realize that you can use "" or "#" to submit the form. Now my question is when writing a php page that has both the handler and the form I was told it was best to write a form action like this:

action="<?php echo $_SERVER['PHP_SELF'] ?>"
//or
action="<?php echo $_SERVER['SCRIPT_NAME'] ?>"

Now why would you need to add this inline script if you could have the form submit to itself using '#' or just simply not setting the form action. I'm just curious, as adding in that php does create bulky and messy looking form code (which is already bulky and messy looking).

I also understand that the alternate '#' and "" could be used in cases that you aren't using PHP, but I guess the real question is why add the PHP if you don't need it (in instances that the form is submitting to a php page).

thanks, Brodie

Mahalo guys for all the responses. I realize that using the PHP code to generate the url is probably (in most cases) the route to take, as all it would take is for an update to a browser or to HTML in general to say "" and "#" are invalid operators for submitting to the root page. Also I know that the '#' is for referencing an anchor on the same page, but I figured I'd see what everyone's take on it was.

Upvotes: 1

Views: 649

Answers (3)

Jon
Jon

Reputation: 437336

First of all the easy part: why put something into the value of action in the first place.

Well, the HTML 4 spec says (emphasis mine):

action = uri

This attribute specifies a form processing agent. User agent behavior for a value other than an HTTP URI is undefined.

Therefore, while practically all browsers will end up submitting the form to the script itself, technically this is a happy coincidence that you should totally not rely on. However, this is not a problem for HTML 5.

In addition, # by itself is not a valid URI as per the W3C's definition, so that should be ruled out as invalid as well.

Now for the other half: how to get the current URL in PHP.

For basic usage, you can use either one of $_SERVER['REQUEST_URI'] and $_SERVER['PHP_SELF'] for this, depending on if you want to preserve any GET parameters in your current URL (PHP_SELF will not include them, but REQUEST_URI will).

In more advanced scenarios (e.g. writing code using a framework) it would be better to use the framework's own URL-generating utility functions to generate the URL for you (this would take routing etc into account, so is preferable).

Update: I misread the HTML 5 spec, which says you can leave the action blank.

Upvotes: 5

hafichuk
hafichuk

Reputation: 10781

tl;dr - Leave it blank.

With modern frameworks and url rewriting, this is actually a bad practice. Your php script will more than likely be different than the URI path to access it.

Upvotes: 0

Richard Edwards
Richard Edwards

Reputation: 2060

Using # is not really the right way to do it, although it will work. You will find that the # on the end of a URL is supposed to be used to scroll the page down to an anchor on the page which matches it. Forms should use a URL in the action field. It's not wrong to do it any other way, but it's more to do with accessibility and usability (some JS librarys use the # url)

Upvotes: 1

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