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#61

April 4th, 2006, 10:34 AM

mateoc15

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Quote:

Originally Posted by chads2k2

#45 - Why can't I use my javascript variables in PHP?

Also, just think about it. In the code sample given by chads2k2 when the PHP page is loaded it is parsed into HTML. At that point your prompt hasn't even been displayed and the user hasn't even had the chance to set your NAME variable, much less let the PHP engine parse it and place it in the place where you're calling $_GET['NAME']. JavaScript is executed after the page is loaded.

Comments on this post

chadsmith729 agrees: Brilliant!

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#62

May 2nd, 2006, 08:05 AM

chadsmith729

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#47 - How do I get PHP to work based upon the location of their IP address.

There are a couple of things that you need to know before you start doing this. The first being that the IP address could be a spoof, or could be based on a proxy server. This means that you will not always be assured to get the IP address of the actual user. The second thing that you must know is that even if you get the IP address it might be from AOL, MSN, Earthlink, ect which setup a block of addresses that always look like they are coming from the United States.

So, if you are going to use this information to determine what language to have your website display you might want to consider these. However, if you evaluated the risks and you see nothing wrong with doing what you are doing then here are some links that can help you out with the code and such:
http://www.maxmind.com/app/geoip_country
They even have a PHP api:
http://www.maxmind.com/app/php

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Last edited by chads2k2 : May 2nd, 2006 at 08:06 AM. Reason: Coloring the top

#63

May 2nd, 2006, 08:55 AM

mateoc15

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Regarding the above post: It's not a good idea to use IP address as a unique identifier of your user because (among many other reasons) dial-up services in particular give dynamic IP addresses. Basically, every time the user connects they get a new IP address.

#64

May 11th, 2006, 10:05 AM

chadsmith729

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#48 - Resizing an image with PHP
Many have asked this in the past and a couple of people have responded in a way that doesn't actually answer the question. The question being, how do I resize an image with PHP? Yes this will work for larger images going to smaller, but smaller images to larger the math doesn't work out really well.

PHP Code:


		
			
<?php

//imageScale (image Location, new image width, new image height)

//You can choose the new Width, or new Height but not both (if you're going by Height, put a -1 for new Width

//will return an array, element 0 is the new width, element 1 is the new height

function imageScale($image, $newWidth, $newHeight)

{

   if(!$size = @getimagesize($image)) die("Unable to get info on image $image");



   $ratio = ($size[0] / $size[1]);



   //scale by height

   if($newWidth == -1)

   {

      $ret[1] = $newHeight;

      $ret[0] = round(($newHeight * $ratio));

   }else if($newHeight == -1){

      $ret[0] = $newWidth;

      $ret[1] = round(($newWidth / $ratio));

   }else{

      die("Scale Error");

   }

   return $ret;

}

?>

PHP Code:


		
			
////  USES

$resize_array = imageScale("images/image_name.jpg",357,-1);

echo "<img src='images/$image_name' width='" . $resize_array[0] . "' height='" . $resize_array[1] . "' alt='Image' />";

Hope that clears it up,
Chad

Last edited by chads2k2 : May 11th, 2006 at 11:21 AM. Reason: Kicken brought up a good point.

#65

May 11th, 2006, 11:18 AM

kicken

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Quote:

Originally Posted by chads2k2

#48 - Resizing an image with PHP

Actually, with that code you don't need the GD library at all.

Quote:

Originally Posted by php manual

Note: The getimagesize() function does not require the GD image library.

Also note, that unless the scaling you're doing is minor (as in only around a 50-100 pixel change) then you'd probably be better off using gd to actually resize the image, for two reasons:

1) The quality will almost certainly be better. Browsers generally do a fast resize resulting in a poor but quick resize operation.
2) You save bandwidth because the file size actually is reduced. By having the browser resize the image, the entire file must still be downloaded rather than just a small thumbnail like version.

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#66

May 11th, 2006, 01:04 PM

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This should give you most of the detail: http://www.tutorialized.com/tutoria...-with-PHP/11878

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#67

July 9th, 2006, 09:19 PM

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#50 - Windows Apache MySQL PHP (NOT XAMPP,WAMP,appserv)

Recently there has been far more discussion about security and setting up a server the proper way than I care to think about again. Every answer seems to be some prebuilt solution that everyone swears is the end all to server setup. I disagree completely with using a premade system such as appserv, XAMPP, WAMP, or anyother system that is developed for the sole purpose of double clicking and having the entire system setup correctly the first time. That is not how you setup a server. Nor will it ever be that way. I mean MySQL, PHP, and Apache are free. You would think that one of them would already have thought about incorporating it all into one package, ask yourself why they haven't done so? It comes down to security for one company may not be secure enough for another, one size does not fit all.

Some have said that it is hard. That by doing this it will be difficult getting it setup. I agree that in the beginning it is a bit difficult, I mean with all the reading you will have to do. The reading that is required is reading the installation text files and maybe a config file or two. Where even those configuration files are so well commented it's amazing. Take the time to read php.ini file line by line. You will walk away with a greater sense of how the system works, moreso that just having something else configure it for you.

I can assure you one thing. If you setup your own server you will gain experience, and knowledge, but more importantly you will gain the self rewarding notion that you took the time to do it right the first time. You didn't cut to the easy way when you had a choice.

Every pre-made system was put together in what they think is a "perfect" system. Will it work for your own server? Sure, but will it be the most secured perfect system for your application? No. Ask any hosting company if they use XAMPP, or WAMP, appserv and they will (or should) laugh at you. It is fine (I guess) for localhost checking to ensure that your scripts work. But what will you say if your boss (present, or future) asks you to setup the server for your companies website? Will you tell them that you double clicked a setup.exe file and you're ready to go? Hopefully not.

Where to get the stuff:
PHP (GET THE ZIP FILE!!!)
Apache2
MySQL 4 or 5

Instructions (other than the install.txt file in PHP's zip)
Very good tutorial! Well written that has easy instructions.
http://www.webmasterstop.com/48.html
http://www.apachemysqlphp.com/

Doing it right the first time will make all the difference in the world,
Chad

Comments on this post

bluedragon agrees: Totally agree : Xampp and the like are great for localhost when starting out . . . but learn how to
do it on your own!

trinisam agrees: Excellent advice...

Last edited by chads2k2 : July 19th, 2006 at 09:06 AM. Reason: Added another tutorial.

#68

October 4th, 2006, 10:36 AM

ManiacDan

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Quote:

Originally Posted by ape2man

#30 How do i str_replace thats not case sensitive

PHP Code:


		
			
/* Was submitted by jpenn : Senior Member */



function stri_replace( $find, $replace, $string )

    {

    $parts = explode( strtolower($find), strtolower($string) );



    $pos = 0;



    foreach( $parts as $key=>$part )

        {

        $parts[ $key ] = substr($string, $pos, strlen($part));

        $pos += strlen($part) + strlen($find);

        }



    return( join( $replace, $parts ) );

}



echo stri_replace( $find, $replace, $string );

Easier, I think, to do a preg_replace with the i modifier:

PHP Code:


		
			
 $new_string = preg_replace("/$find/i", $replace, $original_string);

Faster than jpenn's implementation I think. Although that's pretty good as well.

-Dan

#69

December 29th, 2006, 09:13 AM

srisa

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You can use the inbuilt function str_ireplace(search, replace, source)

#70

May 7th, 2007, 02:52 AM

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Quote:

Originally Posted by scoutt

but to answer you, you can't chmod files in windows. you don't need to.

#51 - Can I change the file permisions/attributes in Windows
There is attrib command in windows to change the file attributes.
Syntax:

Code:

ATTRIB [+r|-r] [+a|-a] [+s|-s] [path\file] /s

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Last edited by helloakash : May 7th, 2007 at 02:54 AM.

#71

September 6th, 2007, 04:18 PM

chadsmith729

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#52 - How do I suppress errors in PHP?

I have been seeing this problem come up a lot and figured I would put this in the FAQ of PHP.

--- The @ symbol:
You can place an @ symbol in front of the function and it will not have the error be displayed. You can view more about this here.

--- error_reporting()
You can use the function error_reporting() to suppress all errors with:

PHP Code:


		
			
 error_reporting(0);

--- Fool proof way
There is one fool proof way of making sure that no errors will show up, that is to test your application throughly. When you test your application as thoroughly as you possibly can you will see most errors (syntax, fatal, ect) and then you can fix your application. You can suppress the errors but you aren't fixing anything, fix the application then if errors exist move to plan B. Remember that errors are coming up for a reason, find out what the error is and fix it. Use one of the above ONLY when your application is ready to go live and you are sure no errors should arise anyway.

Hope this helps,
Chad

#72

September 6th, 2007, 05:19 PM

sryuuza

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Info Post Only: How to Convert Decimal to Time

This post is not a question, but rather an answer to a question I have seen asked but unanswered around the internet.

How do I convert a decimal to time?

PHP Code:


		
			
function makeTime($num){

    //make string into int

    //add hours to return value

    $timeLeft = intval($num).":";

    //subtract string from int, multiply by 60

    $num -= intval($num); $num *= 60;

    //add leading zero if needed

    if(strlen(intval($num))==1){

        $timeLeft .= "0";

    }

    //add minutes to return value

    $timeLeft .= intval($num).":";

    //subtract string from int, multiply by 60

    $num -= intval($num); $num *= 60;

    //add leading zero if needed

    if(strlen(intval($num))==1){

        $timeLeft .= "0";

    }

    //add seconds to return value

    $timeLeft .= intval($num);

    //return final string.

    return $timeLeft;

}



echo makeTime(1.5); //prints "1:30:00"

echo makeTime(23.7111111); //prints "23:42:39"

Enjoy!

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#73

September 6th, 2007, 05:31 PM

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Following on from the above, if you're going to use the @ operator, you should manually test return values.

Eg. some older libraries are happy to chuck a warning if something isn't perfect (like really old versions of the older 'mysql' library which would chuck a warning if you tried to use mysql_fetch_<whatever> on a result object that returned no rows. In fact the easiest way to do this is something like the following:

php Code:

Original - php Code
if ($row = @ mysql_fetch_assoc($result)) { //do something }

if ($row = @ mysql_fetch_assoc($result))
{
  //do something
}

This provides safety and also handles the problem of 'what if i reached the last row?'.

I tend to do something similar to the above (wrapped around my homemade database class) in a while loop:

php Code:

Original - php Code
while ($row = $db->next) { echo "Hello, {$row->name}!"; }

while ($row = $db->next)
{
  echo "Hello, {$row->name}!";
}

The reason the above work is because a non-empty array counts as true in a boolean context, so when you get passed false (the only other possibility than a non-empty array), the loop terminates. My database class returns a resultset class which functions like mysql_fetch_object but has more functionality, and the same applies here, my class returns false if there are no more rows.

#74

September 6th, 2007, 05:31 PM

codergeek42

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Don't forget about strftime and mktime.

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#75

September 6th, 2007, 05:50 PM

sryuuza

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I apologize if this is posted in the wrong area, I did not realize there was a specific section for answers...

as for mktime and strftime they don't exactly work in the same way. To my knowledge neither are about to handle decimal to time conversion out of the box. mktime requires you to specify hour, min, sec and so on individually.

If you know of a shortcut to performing this outside of a function, or a way to optimize the function using either one of these, please let me know.

Thanks

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