JScript vs. PHP

Anon

While trying to find an "easy" solution to duplicating my browser's "back" button using PHP, someone here turned me onto JavaScript (JS). Using the JS history object, this is a trivial task.

I am now coming to the conclusion that client side scripting, such as JS provides, can be even more powerful than the server side scripting that PHP offers. But, and that's a big but, I see I still the need PHP for server side operations like e-mail, file I/O, DB support, etc. So I am going to happily marry these two technologies together for what I hope is a winning web site.

My question is, for you JS folks, does JS allow for "modularizing" common sets of functions and then including the file that contains them wherever needed? As an old C++ programmer, I like this feature of PHP very much. But I don't know if JS supports this approach (I'm new at JS).

All comments are welcomed.

And please, I don't mean to start a "holy" war here between JS and PHP :-) I love my <? PHP ?>

brandonschnell

in the <HEAD> </HEAD> tag include a script src tag like so:
<SCRIPT SRC="javascript_functions.js"></SCRIPT>

the .js file can include common javascript functions. just call your javascript functions normally on your web page after that.

Anon

On that note, I have a javascript&PHP question...

I have a set of checkboxes, all with the name 'list', and each containing different values. I use javascript to select all of the boxes via a button, but it seems only the last checked item gets put into $list, instead of making it an array

my code is below - doesn anyone have any ideas?

Thanks,
Jason

<head>
<SCRIPT LANGUAGE="JavaScript">



</script>
</head>
<body>
<input type="checkbox" name="list" value="1">
<input type="checkbox" name="list" value="2">
<input type="checkbox" name="list" value="3">
<input type="checkbox" name="list" value="4">
<input type="checkbox" name="list" value="5">
<input type="checkbox" name="list" value="6">
<input type="checkbox" name="list" value="7">

<input type=button value="Check All" onClick="this.value=check(this.form.list">

</body>

There is a submit button that sends this info ao another page, but everything after this script is irrelevent in my problem.

Thanks again,
Jason

kparker

No need to start a rwar, because the question 'which is better/more powerful' is completely irrelevant. Each addresses a different side of the processing picture. Some things can only be done on the client side, some can only be done on the server side, and a few can happen either place.

I have only one caution here: don't place any reliance on JS for data validation, however, since the client can turn it off. Or rather, you can use JS validation as a convenience in addition to checking at the server, but if you get rid of the server-side checking you're just begging for bad data to sneak into your system.

egervari

JS checking is good when you know your environment. A lot of information can be known if you know who your clients are. For instance, a JS application is good if you are developing an extranet for a company where you know they all use IE and have Javascript turned on. It's definiately much cleaner to write that kind of stuff on the client side. I'm not saying you don't have to check on the server.. you should. But it's good for various things.

yclin

Try this,

<input type="checkbox" name="list[]" value="1">
<input type="checkbox" name="list[]" value="2">
....

Then you should be able to use $list as an
array in your PHP script.
Hope this will help.

-Yung

Anon

The JS Bible says that data validation is one reason you WANT to use JS, because it can be much quicker, especially if your web site is very busy.

Currently, I am doing all my validation with PHP and thought of redoing this in JS. But your warning made me take notice!

How exactly could a customer turn this validation off? Do you mean they can simply turn off JS altogether in the browser? And if that is true, then none of my JS would work for them, right?

I never bothered to check the options for IE on this (at least not for JS) but I'm going to do this right after I post this. This could be very troubling indeed.

Anon

That bit of info does not seem to appear anywhere in the tutorials. And yet with the nature of browsers being object oriented (window obj, doc obj, form obj, etc.) you would think this would be one of the first topics covered.

Question: since this script src tag must go inside <HEAD> then I take it that you must do this for each and every page where you want to use your set of functions?

This looks similar to PHP's <? include 'my_functions.php' ?> construction for each page.

Also, is the .js extension just by convention, or can it be anything you want?

Thanks again.

Anon

I ve tried that with no luck.
I also tried adding <? $list = array(); ?> at the beginning of the script with no luck...

I can't think of any reason why list isnt storing the values as an array...

Let me know what ya think

Thanks,
Jason B

yclin

I just tried the following test HTML and PHP,
they worked just fine for me.
(FYI, I'm using PHP 4.0.4.)

HTML: test_array.html

<head>
<title>
Passing an Array to PHP
</title>
</head>

<body>

PHP: test_array.php

<?php
for ($i = 0; $i < sizeof($list); $i++) {
echo $list[$i] . "<br>\n";
}

-Yung

Anon

Actually, you can place the script tag anywhere you want. It'll execute in the order it is called.

It doesn't appear in JavaScript tutorials, because it's an HTML convention. Though you would think it would be referred to...

Yes, this tag will have to be placed on every page from which you want to call the script.

.js is the only extension I've ever seen used, but I'm no expert here.

kparker

This could be very troubling indeed.

Be troubled. Be very troubled. If, as Ken says, you completely control the client environment... but even there, the individual user can still go into their IE or Netscape configurations and turn javascript execution off.

kparker

The JS Bible says that data validation is one reason you WANT to use
JS, because it can be much quicker, especially if your web site is very
busy.

It's quicker even if your web server is blindingly fast, and no one else is browsing the site or otherwise using the server. But the speed from JS comes more from two things:

(1) It happens in memory on the client machine, rather than requiring a round-trip tcp transaction to the server, plus starting and running the php script on the server.

(2--this is the real biggie) It can be done on a field-by-field basis, whereas any validation on the server side only happens after you've completed the form and posted it back to the server (can anyone say "IBM mainframe block-mode terminals? I thought we left all that behind!!!")

Anon

If you make a system dependent on js, you can first check to see if the user has javascript enabled by trying to use "document.location" and send them to the rest of your system that requires javascript. If they don't get redirected, then the rest of the page will display where you can inform them that they are unable to use your system since javascript has been disabled.

<HEAD>
<SCRIPT LANGUAGE=JavaScript>
document.location="page_with_js.html";
</SCRIPT>
</HEAD>
<BODY>
<p>Your Browser has JavaScript turned off.</p>
</BODY>

jc94062

Or if JS isn't enabled redirect em to a PHP checker page...

I think a mixture is best, for things like checking the length, use html, maxlength="10" to make sure it isn't too long, and then maybe php to make sure its too short (for an ICQ field for example, I don't know of any ICQ numbers over 10 digits, or under 6 digits)

Maybe then use JS for checking the mail address, just an idea.

Anon

However, with clientside checking you must trust the client. which is not always possible.

Anon

First of all, I hope that a year later IS too late to help you. I'm posting this to be of assistance to anybody searching through these messages with the same problem.

The problem has nothing to do with the jscript. The problem has to do with the fact that PHP does not understand that "list" is supposed to be an array. It interprets it as a string value, and thus overwrites itself with each value, until it winds up equal to the last value you have listed there. Change the name of your input to "list[]", and PHP will understand that this should be read in as an array.