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#31

June 22nd, 2003, 08:27 PM

esha

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What should I do if I am getting this fatal error:Fatal error: Cannot redeclare <bold>somefunction()</bold> (previously declared in \somewhere\filename.php:line x) in \somewhere\filename.php:line x?

It means you have the same include file in two places.
for example let us say you have a file name index.php

and in index.php:
<php>
include("file1.php");
include("file2.php");
</php>
and then let us say in file1.php:
<php>
include("file2.php");
</php>
then you will get this fatal error. all you need to do is comment out include file2.php inside file1.

#32

August 5th, 2003, 10:45 AM

drgroove

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Quote:

Originally posted by AlCapone
#24 How do I make prev/next links?

General code would be something like this:

PHP Code:

mysql_connect('localhost') or die('cant connect');;#,'user','pass'); mysql_select_db('one'); $perPage=1; $start=isset($HTTP_GET_VARS['s'])?$HTTP_GET_VARS['s']:0; $total_rows=isset($HTTP_GET_VARS['t'])?$HTTP_GET_VARS['t']:''; $PHP_SELF=isset($HTTP_SERVER_VARS['PHP_SELF'])?$HTTP_SERVER_VARS['PHP_SELF']:''; if(!$total_rows) list($total_rows)=mysql_fetch_row(mysql_query('select count(*) from user')); $result=mysql_query("select * from user limit $start,$perPage"); while ($data=mysql_fetch_assoc($result)) echo $data['username'];//output data here $startP=$start-$perPage; echo $startP>=0? "<a href='$PHP_SELF?t=$total_rows&s=$startP'>PREV</a> " : 'PREV '; $startN=$start+$perPage; echo $startN<$total_rows ? "<a href='$PHP_SELF?t=$total_rows&s=$startN'>NEXT</a> " : 'NEXT ';?>

Several things you need to be aware of:
Firstly, as you see I've decided to pass total # of records through url in sake of saving some time and load for mysql and not requesting to count rows every time. I do not think this could cause any problems, but it surely will take the load off of sql db.

And secondly, you can as well make it work through POST so that none of the variables show up in the URI, but it is up to you to decide which is *the way*, personally I dont see any advantages of one over another. Good luck reaching max url size with just search keywords.

edited for better code

Joao Prado Maia posted code on O'Reilly which also accomplishes this task - as this is easily one of the most asked questions, I thought to post a link to his PHP class for this functionality, as an addendum to AlCapone's own code.

PHP Pagination Class

Its fairly straightforward to implement and highly portable - JPM also allows use of this free of charge.

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#33

September 19th, 2003, 02:34 AM

paCkeTroUTer

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How to Populate a Multiple Select Option Box from the Database

#39 How to Populate a Multiple Select Option Box from the Database

This is an example of how to populate a Multi-Select Option Box from the database. A few times it has been asked in the forum but not been given a complete example. Hope this helps someone.

PHP Code:


		
			
<?php

    // Connect to Database ###########################################################

        require ('norka.php');

    // Connect to Database ###########################################################

    

    echo "<select name=\"select_products[]\"  size=\"5\" style=\"width: 160px;\" multiple >";

    

    //query for All the products                                

    $get_all_pdts = "Select id, pdt_name from norka_products where pdt_status = '1'";

    $exe_get_all_pdts = mysql_query($get_all_pdts);



    //query for the Products to be selected  ## Change per your requirements ##

    $get_selected_pdts = "SELECT norka_gallery_products.pdt_id 

                FROM norka_gallery_products, norka_gallery_pics 

                WHERE norka_gallery_products.pic_id = norka_gallery_pics.pic_id 

                and norka_gallery_pics.image_link ='" . "gallery/car_wash.jpg" . "'";                            

    $exe_get_selected_pdts = mysql_query($get_selected_pdts);

    

    while($selected_pdts = mysql_fetch_array($exe_get_selected_pdts))

    {

        //Get the values which need to be selected into an array

        $selected_array[] = $selected_pdts['pdt_id'];

    }

            

    while($all_pdts = mysql_fetch_array($exe_get_all_pdts)) //All the records

    {

        $value = $all_pdts['id'];

        $name = $all_pdts['pdt_name'];

        if(sizeof($selected_array) > 0)

        {

            if (in_array($value, $selected_array)) 

            { 

                print "<option value=\"$value\" selected>" . $name . "</option>\n";                

            } 

            else 

            { 

                print "<option value=\"$value\">" . $name . "</option>\n";                 

            } 

        }

        else

        {

            print "<option value=\"$value\">" . $name . "</option>\n";  

        }

    }

        

    mysql_free_result($exe_get_all_pdts);

    mysql_free_result($exe_get_selected_pdts);

    echo "</select>";

?>

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#34

November 26th, 2003, 01:46 PM

melsana

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Quote:

Originally posted by Sepodati
#20. Should I use echo or print?
Doesn't matter, they are the same.

I find it very useful to use one for my main output and the other for my debug statments that way I can easily search for debug statements and comment them out or use them.

Comments on this post

dotancohen agrees: good idea

#35

January 27th, 2004, 11:17 PM

codergeek42

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Send a message via Google Talk to codergeek42

I find melsana's idea of differentiating between the two for normal/debug output hepful, because I use echo for everything normally and print for all my debug output, so in my IDE, i can just do a search and replace all occurences of "print(" with "//print(" to comment all debug statements. It makes my coding easier to do search-replacing.

Good post.

#36

February 23rd, 2004, 05:50 PM

moejoe

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CHmod in win2k?

Hi, how do i set CHmod (FIle Permissions) on Windows 2000 with APache 2/PHP and mysgl install on my personal webserver as i cant do it from my ftp client as its fro unix only

if i cant do it in windows 2000, i might hav to change my server OS to linux

cheers

moe

#37

February 24th, 2004, 01:12 PM

scoutt

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this is a FAQ, not a thread to ask questions.

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

Comments on this post

helloakash disagrees: There is attrib command. And we need to change permissions sometimes

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#38

April 6th, 2004, 03:31 PM

saintp

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#40. I put some text into a database, and when I pull it out all the newlines are gone! Ack!

A: No, they aren't. HTML treats newlines as generic whitespace. If you view your source, they're still there. Luckily, PHP provides a handy function, nl2br() that lets you convert newlines to HTML linebreak tags.

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#39

April 6th, 2004, 04:01 PM

Sepodati

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Quote:

Originally Posted by saintp

PHP provides a handy function, nl2br() that lets you convert newlines to HTML linebreak tags.

PHP actually just adds in the <br /> tag and doesn't "convert" the newlines; they're still there. Just so everyone's on the same page.

---John Holmes...

#40

April 20th, 2004, 04:01 PM

saintp

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#41. How do I make a select list/drop down menu autopopulate depending on the value of another select list?

This one must come up three times a day.

Here is real code that I have used to great success; this snippet comes from a system that lets students in some of our chemistry courses do their labs via a PHP app. This snippet is from the administrative-side "edit a lab" script. I've tried to remove all custom functions

PHP Code:


		
			
//************** start dynamic drop-down list magic ***************// 

  print "<script language=\"javascript\"><!--\n"; 

  $classes = mysql_query("SELECT class FROM classes ORDER BY class"); 

  print "var labIDs = new Array(" . mysql_num_rows($classes) . ");\n"; 

  print "var labNames = new Array(" . mysql_num_rows($classes) . ");\n"; 

  while (list($class) = mysql_fetch_array($classes)) { 

     $labs = mysql_query("SELECT DISTINCT labID FROM duedates WHERE class = $class ORDER BY due"); 

     print "labIDs[$class] = new Array(" . (sizeof($labs) + 1) . ");\n"; 

     print "labNames[$class] = new Array(" . (sizeof($labs) + 1) . ");\n"; 

     $i = 1; 

     print "labIDs[$class][0] = 0;\n"; 

     print "labNames[$class][0] = 0;\n"; 

     while (list($lab) = mysql_fetch_array($labs)) { 

        print "labIDs[$class][$i] = '$lab';\n"; 

        print "labNames[$class][" . $i++ . "] = '"; 

        print addslashes(mysql_result(mysql_query("SELECT name FROM labs WHERE class = $class AND labID = $lab"), 1)); 

        print "';\n"; 

     } 

  } 

  print <<<EOJS 

function clean(what) { 

  for (; what.options.length > 1;) { 

     what.options[what.options.length - 1] = null; 

  } 

} 



function updateLabs(which) { 

  with (document.forms[0]) { 

     clean(which); 

     curClass = course.options[course.selectedIndex].value; 

     for (var i = 1; i < labIDs[curClass].length; i++) { 

       which.options[which.options.length] = new Option(labIDs[curClass][i] + ". " + labNames[curClass][i], labIDs[curClass][i]); 

     } 

  } 

} 

//--></script> 

EOJS;  //************** end dynamic drop-down list magic ***************// 



  print form_open(); 

  //replace the old static drop-down tag with a new dynamic one 

  print "Course: <select name=\"course\" onChange=\"javascript: updateLabs(lab);\">\n";

  $classes = mysql_query("SELECT class FROM classes ORDER BY class")

  print "<option value=0 selected>Choose one:</option>\n";

  while (list($class) = mysql_fetch_assoc($classes)) {

    print "<option value=$class>$class</option>\n"