This is a very simple javascript - script, which can help us to resize any image (picture) included on our web-page "automatecally" by getting the visιtor's(client side) dimensions Height + Width and so changing the image proportionally .

Ok, so here's the deal. I've started to dally with Flash a bit, and I'm feeling all naked without my nifty Prototype functionality.

Most important to me are the bind() and curry() functions (though, others will rear their heads as my AS code gets more complex), Object.extend, and $A. They are para-ported here.

The following script is a single interface for pre-validating any HTML form. It lets you validate your form data the way you want, while handling the rudimentary tasks itself.

1) Change just one variable to make it work with $_GET or $_POST or $_REQUEST.

2) Name which elements are 'required' all at once in a hidden HTML text input.

3) Easily provide field descriptions in hidden HTML text inputs that you can use to print error statements.

4) Call a single function to print out error statements that you can easily style with CSS.

5) It automatically checks if fields marked 'required' have been filled out.

Most of the pre-validation code is from PHP 5: Unleashed by Sams Publishing. I found it extremely useful for a recent project. Sharing it here, I removed some unnecessary functions, and tried to simplify some points.

All the comments are my own; hopefully I provided more than enough explanation.

This is a version of my previous entrant, Promise, that will work with prototype, but does not require it. It's slightly more advanced, using .apply here and there.

It's basically a function to allow any other function to poll. Polling is generally regarded as bad practice in object oriented code, but can make very simple the matter of, for example, running a bit of code only after a single-run event (like onload) occurs (whether that be in the future or past), another unrelated bit of code needs to be hack-tracked, or any other generic condition.

Note that when the function runs, it doesn't necessarily run within the scope that's called it. Its context is set to itself, rather than its normal context, and it's asynchronous, so you'll not get a return value. If you use Prototype, you can bind the function and it'll behave as it should in terms of context, but I'm unaware of a way to cause an asynch function to block execution - and you'd really rather that not happen anyway, trust me.

AJAX based submit form and use PHP to get results...

Very easy to use and understand, hope you will find it useful and easily edit it to fit your needs.

This is the final version of my Javascript serializer targetted at PHP.

The point:

Objects are most easily passed over the network as serialized strings. Between serialization and unserialization, serialization is by far the easier of the two. Since object passing can sometimes be a process-hungry thing, we want to do things as quickly as possible.

My solution is to always do the hard part in compiled code, while doing the easy part in script. That is, whichever way you're passing an Object, you want to pass it in a natively decoded format for the target.

Since I work mostly in PHP, this meant writing a module that would be able to generate a string that can be decoded with PHP's unserialize() function into a PHP Associative Array (or other applicable type).

Notes:

This lib REQUIRES the Prototype lib. You can hack prototype out of it, of course (by replacing the references to Object.extend() with explicit assignments), but I can't imagine why you'd want to bother; it's used mostly with Ajax.Request anyway.

Previous versions of this code would add the .toPHP() member to the Object prototype. After trying to enumerate things, I found that this is a REALLY bad thing to do, as toPHP springs up where it's not wanted in ALL objects. As a result, I've opted to go the Prototype route and apply it as a member of the Object object.

Please note that if you pass a serialized string to PHP via GET or POST, you'll need to stripslashes() before unserialization.

Javascript sample of use:

var myObject = {
name:'value',
test:['Array','of','strings'],
bool:false,
timestamp: new Date(),
float: 3.1415926539,
number: 42,
func: function () {
alert('Member functions are always omitted from serialization');
}
}
alert(Object.toPHP(myObject));

Output:

a:7:{s:4:"name";s:5:"value";s:4:"test";a:3:{i:0;s:5:"Array";i:1;s:2:"of";i:2;s:7:"strings";}s:4:"bool";b:0;s:9:"timestamp";i:1190897619824;s:5:"float";d:3.1415926539;s:6:"number";i:42;s:4:"func";null}

Sample of subsequent unserialization in PHP (passed via POST as 'myobject')

$myObject=unserialize(stripslashes($_POST['myobject']));
var_dump($myObject);

Output:

array(7) {
["name"]=>
string(5) "value"
["test"]=>
array(3) {
[0]=>
string(5) "Array"
[1]=>
string(2) "of"
[2]=>
string(7) "strings"
}
["bool"]=>
bool(false)
["timestamp"]=>
int(1192296601)
["float"]=>
float(3.1415926539)
["number"]=>
int(42)
["func"]=>
NULL
}

Ok, so I was getting frustrated with the inability to hide data in javascript, as well as a number of other concerns with existing class structures (the requirement to use this.constructor in lieu of self, for example).

As a result, I've thrown together a nice little class constructor that accepts a class definition, as well as a class extender that allows you to build a new class from an existing one, with full access to all that private stuff.

Here's a quick lil' addon for Prototype that I use often.

Prototype.Promise(condition, action, interval)
condition is a string that you want met before an action is run.
action is a function that does the action.
interval is the polling rate for condition in seconds, and defaults to 1

So, for example, you may want function foo to run, but only once bar has been set:

function foo(a,b) {
this.retVal=a+b;
}
var thingy = {
retVal:0
};
Prototype.Promise(
'thingy.retVal=5',
foo.bind(thingy,5,10),
5
);


Then, in some point in the mysterious future, thingy.retVal gets set to 5, at which point, the Promise goes into effect, and thingy.retVal becomes 10.

Where I find this particularly useful is in making sure that a document is loaded before doing something (condition="$$('body').length>=1), as you can see it used for the include functions.

Speaking of which, the following include functions are great for getting scripts and stylesheets into your page. I won't bother with examples, as they're pretty straightforward.

Meanwhile, Prototype.scriptPath will point to wherever in your server's heirarchy Prototype was loaded from. The regex, you'll note allows for names like prototype.compressed.js, prototype.modified.js, 2007-09-28.prototype.js, etc - just in case you want to keep track of your various hacks of Prototype, as I do.

ZeroField

This is a correct way to do login form auto-focus, checking to see if either username or password have focus already. This prevents someone from typing a username hitting TAB, then having JavaScript chime in, resetting focus to Username while user is typing in their password. In this case, the password is appended to the username which is in plaintext.