http://blog.ramonlechuga.com JavaScript / HTML / CSS / PHP Wed, 16 Nov 2011 00:58:16 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 DOM Methods vs innerHTML http://blog.ramonlechuga.com/2011/11/04/dom-methods-vs-innerhtml/ http://blog.ramonlechuga.com/2011/11/04/dom-methods-vs-innerhtml/#comments Fri, 04 Nov 2011 16:49:56 +0000 Ramon Lechuga http://blog.ramonlechuga.com/?p=153 Finding a fast way to create elements, every browser works differently and this can make some simple tasks fast or slow, I find sometimes a hard dilema using innerHTML I know is easy and lazy for programmers in the other hand the DOM methods such a createElement, appendChild, createTextNode are elegant, understandable but is just to much code for a small piece of HTML maybe templating your HTML would be better.

Anyway I did some speed tests with the following code (you should try it).

(function () {
    var timer       = 0,
        endTimer    = 0,
        iterations = 100000,
        i           = 0;
    //DOM Methods
    var ul = document.createElement('ul')  
    timer = +new Date;
    while (i < iterations ) {
        var
        li_1 = document.createElement('li'),
        li_2 = document.createElement('li'),
        li_3 = document.createElement('li'),
        li_4 = document.createElement('li');
        ul.appendChild(li_1);
        ul.appendChild(li_2);
        ul.appendChild(li_3);
        ul.appendChild(li_4);
        i++;
    }
    endTimer = (+new Date) -  timer;
    console.log(endTimer);
   
    //innerHTML
    i = 0;
    timer = 0;
    endTimer = 0;
   
    var ul = document.createElement('ul');
    timer = +new Date;
    while (i < iterations ) {
        ul.innerHTML ="<li></li><li></li><li></li><li></li>";
        i++;
    }
    endTimer =  (+new Date) - timer;
    console.log(endTimer);
}());

//Chrome
690 ms //Dom Methods
1577 ms //innerHTML

//Opera
1930 ms //Dom Methods
1819 ms //innerHTML

//Firefox
538 ms //Dom Methods
3300 ms //innerHTML

//Safari
782 ms //DOM Methods
722 ms //innerHTML

JSPERF TESTS
http://jsperf.com/innerhtml-vs-createelement-appendchild

After few days testing DOM Methods speed WINS, but the code is just to big so we need to use a js minifier like
http://www.crockford.com/javascript/jsmin.html
http://jscompress.com/
to reduce your script size and speed up the download.

I'm currently working in a simple tool that converts your HTML string to DOM Methods but it just work in the browser I'm taking advantage of the browser DOM parser, I guess I'll require a DOM Parser if I want to run it in another environment, you can check it here.
http://labs.ramonlechuga.com/DOMMethodfy/
Source:
https://github.com/alejandrolechuga/DOMMethodfy

]]> http://blog.ramonlechuga.com/2011/11/04/dom-methods-vs-innerhtml/feed/ 0 Checking object properties http://blog.ramonlechuga.com/2010/10/20/checking-object-structure/ http://blog.ramonlechuga.com/2010/10/20/checking-object-structure/#comments Wed, 20 Oct 2010 18:56:46 +0000 Ramon Lechuga http://blog.ramonlechuga.com/?p=137 When I'm working with an object and I need to check a property, I cannot go straight up I always first check if this one exists, but we have different ways to check them, before I used to do this.

   if (object.property) {
       //exists
       console.log(object.property);
   }

It works when the property is undefined, but if the property has false ,zero(0), or empty string ("") it wont work as we wanted.

Other way is checking if it has its own property by using

if (object.hasOwnProperty("property")) {
   //exists
   console.log(object.property);
}

But here you are just checking the properties that come with the object, not the ones that are inherited by the prototype chain. So in case you want to check all the properties use this code.

if ("property" in object) {
   //exists
   console.log(object.property);
}

It's really annoying checking long objects structures

   var object = {
  data: {
    item: {
      sub_item: {
        bla: {
          here : {
            iam: true
          }
        }
      }
    }
  }
};  
// This could throw us a Reference Error
if (data.item.sub_item.bla.here.iam) {
  //it works
}
//Other way could be...
if (data)
  if ("item" in data)
     if ("sub_item" in data.item)
       if ("bla" in data.item.sub_item)
          if ("here" in data.item.sub_item.bla) {
             //don't do this
          }

Try this snippet:

Array.prototype.some = function(fn, thisObj) {
  var scope = thisObj || window;
  for ( var i=0, j=this.length; i < j; ++i ) {
    if ( fn.call(scope, this[i], i, this) ) {
      return true;
    }
  }
  return false;
};
function isSet (object, string) {
  if (!object) return false;
  var childs = string.split('.');
  if (childs.length > 0 ) {
    return !childs.some(function (item) {
      if (item in object) {
        object = object[item];
        return false;
      } else return true;
    });
  } else if (string in object) {
    return true;
  } else return false;
}

var object = {
  data: {
    item: {
      sub_item: {
        bla: {
          here : {
            iam: true
          }
        }
      }
    }
  }
};

console.log(isSet(object,'data.item')); // true
console.log(isSet(object,'x')); // false
console.log(isSet(object,'data.item')); // true
console.log(isSet(object,'data.item.sub_item.bla.here.iam')); // true
]]> http://blog.ramonlechuga.com/2010/10/20/checking-object-structure/feed/ 3 Private & public properties for JavaScript http://blog.ramonlechuga.com/2010/08/12/private-public-properties-for-javascript/ http://blog.ramonlechuga.com/2010/08/12/private-public-properties-for-javascript/#comments Thu, 12 Aug 2010 16:19:45 +0000 Ramon Lechuga http://blog.ramonlechuga.com/?p=113 Here we have a good article about keeping private properties in your JavaScript kinda Java , well we know that JavaScript is not enough good for Object Orientation but it has a lot good parts :) is very flexible.

Here we have the normal way for making "Classes"

var myClass = function () {
    //this is like the constructor
};
myClass.prototype.myMethod = function () {
   //wow a method :D
};
var myClassInstance = new myClass();

Well we know that everybody who use firebug or javascript pretty often could have access to this objects, so a good way for keep this objects not accesible to the window parent object.. is doing this

(function(){
    var myClass = function () {
        //this is like the constructor
    };
    myClass.prototype.myMethod = function () {
       //wow a method :D
    };
    var myClassInstance = new myClass();
});

And this way is to keep your properties private even from your own objects (I took this method from the Douglas Crockford website), the problem here is that you just access from public to private properties, and private don't have access to public.

var myClass = (function () {
    function privateMethod() {
        alert("Hello I'm the private method");
    }
    return {
        variable:1,        
        method: function () {
              alert(this.variable); // shows 1
        },
        methodCallPrivate: function () {
            privateMethod();
        }
    }
});
var myClassInstance = new myClass();
myClassInstance.method(); // shows 1
myClassInstance.methodCallPrivate(); //shows "Hello I'm the private method"

But I found this way if you want both have access to each other

var myClass = (function () {
    var _public = {};
    var _private = {};
    _public.pubVariable = "Hello World from _public.pubVariable";
    _private.priVariable = "Hello World from _private.priVariable";
    _public.pubMethod= function() {
        alert(_private.priVariable);
    };
    _private.priMethod = function() {
        alert(_public.pubVariable);
    };
    _public.callpriMethod = function() {
        _private.priMethod();    
    };
    return _public;
});
var myClassInstance = new myClass();
myClassInstance.pubMethod(); // shows "Hello World from _private.priVariable"
myClassInstance.callpriMethod(); // shows "Hello World from _private.priVariable"
myClassInstance.priMethod(); //Throws an Error
]]> http://blog.ramonlechuga.com/2010/08/12/private-public-properties-for-javascript/feed/ 5 PHP Error Handler, Tracking you project bugs http://blog.ramonlechuga.com/2010/05/24/php-error-handler-tracking-you-project-bugs/ http://blog.ramonlechuga.com/2010/05/24/php-error-handler-tracking-you-project-bugs/#comments Tue, 25 May 2010 01:11:28 +0000 Ramon Lechuga http://blog.ramonlechuga.com/?p=75 Errors

There’s a way to hide those ugly error outputs from PHP, and not just that you can track them, log them and manage them.

We have different type of errors some of them are possible to catch and others aren’t, in this post you will learn how to build your own error tracker, but first lets learn something about PHP errors, check the different type of errors in the following list.

Value Constant Description PHP
1 E_ERROR Fatal run-time errors. Errors that cannot be recovered from. Execution of the script is halted
2 E_WARNING Non-fatal run-time errors. Execution of the script is not halted
4 E_PARSE Compile-time parse errors. Parse errors should only be generated by the parser
8 E_NOTICE Run-time notices. The script found something that might be an error, but could also happen when running a script normally
16 E_CORE_ERROR Fatal errors at PHP startup. This is like an E_ERROR in the PHP core 4
32 E_CORE_WARNING Non-fatal errors at PHP startup. This is like an E_WARNING in the PHP core 4
64 E_COMPILE_ERROR Fatal compile-time errors. This is like an E_ERROR generated by the Zend Scripting Engine 4
128 E_COMPILE_WARNING Non-fatal compile-time errors. This is like an E_WARNING generated by the Zend Scripting Engine 4
256 E_USER_ERROR Fatal user-generated error. This is like an E_ERROR set by the programmer using the PHP function trigger_error() 4
512 E_USER_WARNING Non-fatal user-generated warning. This is like an E_WARNING set by the programmer using the PHP function trigger_error() 4
1024 E_USER_NOTICE User-generated notice. This is like an E_NOTICE set by the programmer using the PHP function trigger_error() 4
2048 E_STRICT Run-time notices. PHP suggest changes to your code to help interoperability and compatibility of the code 5
4096 E_RECOVERABLE_ERROR Catchable fatal error. This is like an E_ERROR but can be caught by a user defined handle (see also set_error_handler()) 5
6143 E_ALL All errors and warnings, except of level E_STRICT 5

The error_reporting function has a parameter to set which type of error you want to show.

You can set to 0 if you don’t want to show nothing

error_reporting(0);

To show the common errors

error_reporting(E_ERROR | E_WARNING | E_PARSE);

If you’re picky , this will help you to code better

error_reporting(E_ERROR | E_WARNING | E_PARSE | E_NOTICE);

This is the default set from php.ini

error_reporting(E_ALL  ^ E_NOTICE);

This show everything

error_reporting(E_ALL);

I use this, I care more about these ones

error_reporting(E_ERROR | E_PARSE);


You need to create a new PHP file that's going to handle the errors and you have to load it in every PHP file that runs by itself  I mean that is not loaded in another PHP (but don't worry using require_once it will be loaded just once)...but well this depends of the structure of your project .

//At the beginning of your php code
require_once('error_handler.php');

There's a function called set_error_handler with this one you can catch many errors but  there are some E_FATAL errors that are impossible to catch with this function, so theres a trick to catch them and show something else instead.

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ini_set('display_errors', 'On');
#here we are setting our normal error handler
set_error_handler('errorHandler');
#here we wrap the the error in tags
ini_set('error_prepend_string', '<phpfatalerror>');
ini_set('error_append_string', '</phpfatalerror>');
#and all the output will pass through here our fatal error handler
ob_start('fatalErrorHandler');

So in your function you should classified which kind of error you are receiving

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    function errorHandler($error_number, $error_string, $error_file, $error_line, $error_context)
    {
        $error_title    = "";
        $error_array    = array();
        $backtrace      = array();
       
        switch ($error_number)
        {
            case E_FATAL:
                $error_title = "Fatal Error";
                break;
            case E_ERROR:              
                $error_title = "Error";                  
                break;
            case E_WARNING:            
                $error_title = "Warning";                
                break;
            case E_PARSE:              
                $error_title = "Parse Error";            
                break;
            case E_NOTICE:              
                $error_title = "Notice";                
                break;
            case E_CORE_ERROR:          
                $error_title = "Core Error";            
                break;
            case E_CORE_WARNING:        
                $error_title = "Core Warning";          
                break;
            case E_COMPILE_ERROR:      
                $error_title = "Compile Error";          
                break;
            case E_COMPILE_WARNING:    
                $error_title = "Compile Warning";        
                break;
            case E_USER_ERROR:          
                $error_title = "User Error";            
                break;
            case E_USER_WARNING:        
                $error_title = "User Warning";          
                break;
            case E_USER_NOTICE:        
                $error_title = "User Notice";            
                break;
            case E_STRICT:              
                $error_title = "Strict Notice";          
                break;
            case E_RECOVERABLE_ERROR:  
                $error_title = "Recoverable Error";      
                break;
            default:                    
                $error_title = "Unknown error ($error_number)";
                break;
        }
      //Here you code to track errors
   }

With this code from above you can send emails or log errors in Data Base.

The second function you need is the one it takes the fatal errors from the tags, and we show a custom error html.

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    function fatalErrorHandler($bufferContent)
    {
        define('E_FATAL', 'efatal');
        $output     = $bufferContent;
        $matches    = array();
        $errors     = "";
       
        if ( preg_match('|<phpfatalerror>.*</phpfatalerror>|s', $output, &$matches) )
        {
            foreach ($matches as $match)
            {
                $errors .= strip_tags($match) . "\n\n---\n\n";
            }
           
            $var = errorHandler('efatal', 'Fatal Error', 'unknown', 'unknown', $errors);
            $filename = HTML_DIR . "unavailable.html";
            $handle = fopen($filename, "r");
            $contents = fread($handle, filesize($filename));
            fclose($handle);
            $output =  $contents;
        }
        return $var;
    }

Well if you use this code I fully recommend you to take all the possible variables that might be part of the error.
There's a function call debug_backtrace that returns you the array of all the trace you code did. so I recommend you log it too.

Update: If you are using the PHP version 5.3 or earlier, now comes with the new error levels E_DEPRECATED & E_USER_DEPRECATED

]]> http://blog.ramonlechuga.com/2010/05/24/php-error-handler-tracking-you-project-bugs/feed/ 79 Form submit like AJAX style using an Iframe http://blog.ramonlechuga.com/2010/05/19/form-submit-like-ajax-style-using-an-iframe/ http://blog.ramonlechuga.com/2010/05/19/form-submit-like-ajax-style-using-an-iframe/#comments Wed, 19 May 2010 20:01:00 +0000 Ramon Lechuga http://blog.ramonlechuga.com/?p=39 I remember the first time I start using AJAX it was really really amazing :) till I found that I can't send images just text, well I'll show how to upload a file without refreshing the whole page.

Here is you html form code:

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<form enctype="multipart/form-data" method="post" >
    <input name="image" type="file" />
    <input type="submit" value="Submit" />
</form>

And you have add an Iframe element , doesn't matter in which part of the document but I recommend you put it inside of the form like this, add the target attribute to the form element and put the iframe name attribute as a target, you can hide the iframe with the style display:none.

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<form enctype="multipart/form-data" method="post" target="iframe">
   <input name="image" type="file" />
   <input type="submit" value="Submit" />
   <iframe id="iframe" style="display:none"></iframe>
</form>

Ok the problem is that there's no way to fire the onload event of the iframe (I already tried many ways, and asked many people if you know how please let me know) so you have to do a Script that notice you when the Iframe is ready and not just that, maybe you'll need a response from the server.

So here we have to find a way to receive the data and call back a function when the iframe is loaded.

You can follow this way:

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<form action="submitIframe.php" enctype="multipart/form-data" method="post" target="iframe">
    <input name="image" type="file" />
    <input type="submit" value="Submit" />
    <iframe name="iframe" style="display:none;"></iframe>
</form>
<script>
  function myCallBackFunction(data)
  {
    //put your code here
    alert(data);
  }
</script>

So you need to response something like this:

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<script type="text/javascript">
var data = "<?=$myServerResponse ?>";
parent.myCallBackFunction(data);
</script>

In this case I did it with PHP, this is going to be called within the iframe.

Download code here

]]> http://blog.ramonlechuga.com/2010/05/19/form-submit-like-ajax-style-using-an-iframe/feed/ 38 Welcome to my new blog http://blog.ramonlechuga.com/2010/05/18/welcome-to-my-new-blog/ http://blog.ramonlechuga.com/2010/05/18/welcome-to-my-new-blog/#comments Tue, 18 May 2010 23:11:01 +0000 Ramon Lechuga http://blog.ramonlechuga.com/?p=9 Hello readers, welcome to my new blog. The main reason I created because I want to share & save all the stuff I've learnt about building websites.

I'm going to post good tricks for the following languages:

JavaScript ( AJAX/DHTML)
PHP (OOP/MVC)
HTML/CSS
Flash & Flex

So welcome to anyone who comes along here. Please let me know if I have some mistakes on my posts

Thanks,
Ramon

]]> http://blog.ramonlechuga.com/2010/05/18/welcome-to-my-new-blog/feed/ 2