create a 3 cell table and populate it from an array

[gater]

Hello All.
I am trying to set up a page that will display the 'picture of month' for each month of a given year. I want 3 columns of thumbs. There may be no images or up to 12 images for any given year. The images are in different directories and their location /filename/extension will be extracted from an array. I am not very familiar with the count and foreach functions but I assume this can be done using a variation of those. Any thoughts?
Thanks

[Atli]

Hi Gater. Welcome to TSDN!

Everything is possible, especially in a language as flexible as PHP :)

I'm not exactly sure what you trying to do here. I understand the part where you want to show a 'Picture of the month', but I don't understand how you intend to implement it.

Could you explain in more detail?
Perhaps show us code examples?

[gater]

Hi Gater. Welcome to TSDN!

Everything is possible, especially in a language as flexible as PHP :)

I'm not exactly sure what you trying to do here. I understand the part where you want to show a 'Picture of the month', but I don't understand how you intend to implement it.

Could you explain in more detail?
Perhaps show us code examples?

THanks for your welcome Atli!

I am keeping photos in a gallery, with folders for each month. Each month an image is selected as the Pic of the Month and that file information is entered into the pom DB table along with a description, the contributor etc. That image can then be 'activated' to be displayed on each page of the site in a side bar column as an include. The 'deactivated' or previous months pics are no longer shown except in their gallery folders. All that works fine.

I want to create a page to display all the pom s for a any given year. Depending on the circumstances there may be 1 image or up to twelve. I like the script to determine how many images will be displayed on the page and then create and populate the display table with the correct number of cells and populate them with the images.

Code so far looks like this:

<?$s = "SELECT * FROM pom WHERE year =$_GET['year'] ORDER by date" ;
    $r = mysql_query($s, $connect);
    if(!mysql_num_rows($r))
    {    echo "<p class='warning'>There are currently no entries in the Database </p>";    }
    else
    {
 
    ?>
 <table class="content_box" width="100%">
 <? while($i = mysql_fetch_array($r))
        {
    $fname=$i['fname'];
    $fdir=$i['fdir'];
    $f_ext=$i['f_ext']; 
 
     ?>
    <tr>
        <td><img src="<?echo $fdir;?>/<?echo $fname.$f_ext.;?>"></td>
        <td><img src="<?echo $fdir;?>/<?echo $fname.$f_ext.;?>"></td>
        <td><img src="<?echo $fdir;?>/<?echo $fname.$f_ext.;?>"></td>
     </tr>
     <?
     }
     }
     ?>
     </table>
 

[Atli]

Hi again.

While I'm considering your problem, I have a few notes on your code. A few changes I think you may find interesting.
I've taken your code and made a few modification, adding comments explaining what I did and why.

<?php
#-
# Changed <? to <?php. The <? is called short-tags
#  and is disabled by default in PHP. It is always
#  better to use <?php unless you are 110% sure your
#  code will never be used on a server that you can
#  not change the configuration for.
#-
 
#-
# Switched the wild card sign (*) in your query out for
#  the names of the columns you want to increase efficiency.
#  Using * will return all columns which will return a lot
#  of extra data, increasing the server overhead.
# Also fixed the $_GET['year'] usage. Always use brackets {..}
#  around array elements in strings.
# Dates and strings should also be enclosed in single-quotes
#  in MySQL queries.
#-
$sql = "SELECT fname, fdir, f_ext FROM pom WHERE year = '{$_GET['year']}' ORDER by date" ;
 
#-
# Added a die() call to your mysql_query call.
#  helpfull when debugging.
#- 
$result = mysql_query($s, $connect) or die("Query failed: ". mysql_error($connect));
 
#-
# Changed the variable names. Always try to use
#  descriptive variable names. Badly named variables can
#  cause confusion while debugging or if you need
#  to fix a bug in the future.
#-
if(!mysql_num_rows($r)) {
    echo "<p class='warning'>There are currently no entries in the Database </p>";    
}
else {
    #-
    # Changed the code so that it does not exit the <?php block.
    #  This improves performance, as the PHP parser is not
    #  forced to be switched off and on again just to print out
    #  a single line. I use a echo call instead to print the line.
    #-
     echo '<table class="content_box" width="100%">';
 
     #-
     # Switched the mysql_fetch_array function for it's brother
     #  mysql_fetch_assoc. The latter only returns the associative
     #  array elements, as apposed to the former that returns both
     #  the associative and the numerically indexed elements.
     #  This may slightly increase performance.
     #-
    while($row = mysql_fetch_assoc($result)) {
        #-
        # Removed the variables you created here.
        #  As you already have them in the $row array I felt it
        #  was unnecessary to create separate variables for them
        #-
 
        #-
        # Again, I change the code so that it does not exit the
        #  <?php block, replacing it with a echo call.
        #-
        echo <<<END
    <tr>
        <td><img src="{$row['fdir']}/{$row['fname']}.{$row['f_ext']}"></td>
        <td><img src="{$row['fdir']}/{$row['fname']}.{$row['f_ext']}"></td>
        <td><img src="{$row['fdir']}/{$row['fname']}.{$row['f_ext']}"></td>
    </tr>
END;
    }
 
    # -
    # Added the closing </table> tag here. You
    #  put it at the end of the code, where it
    #  will be printed no matter what, even if the
    #  opening <table> tag is not printed.
    #-
    echo "</table>";
}
?>
 

[gater]

Hi,
Thanks for the detailed reply. There are a couple of things in your edits I was not aware of

• The mysql_fetch_assoc
• the echo >>>end

Both of which I k now I will use frequently from here out!
I am sure your solution will be equally as enlightening!
Thanks

[Atli]

Ok. Assuming I am understanding you correctly, this code may be what you are looking for.

This is basically your code, using the modulus operator (%) to insert new rows after every third cell is printed. It will result in a 3 column table filled with images based on the values fetched from your database. No limit as to how many cells there are.

<?php
# Fetch the thumbs
$sql = "SELECT fname, fdir, f_ext FROM pom WHERE year = '{$_GET['year']}' ORDER by date" ;
$result = mysql_query($sql, $connect) or die("Query failed: ". mysql_error($connect));
 
if(!mysql_num_rows($result)) {
    echo "<p class='warning'>There are currently no entries in the Database </p>";    
}
else {
    # Print the table header
     echo "\n<table class=\"content_box\" width=\"100%\">\n<tr>";
 
     # Print each cell
     $cellIndex = 0;
    while($row = mysql_fetch_assoc($result)) {
        # Add a new row if needed
        if($cellIndex % 3 == 0 and $cellIndex > 0) {
            echo "\n</tr>\n<tr>";
        }
        $cellIndex++;
 
        # Print the current cell
        echo "\n\t<td><img src=\"{$row['fdir']}/{$row['fname']}.{$row['f_ext']}\"></td>";
    }
 
    # Make sure the row is not missing cells
    while($cellIndex % 3 != 0) {
        echo "\n\t<td>&nbsp;</td>";
        $cellIndex++;
    }
 
    # Print the table footer
    echo "\n</tr>\n</table>";
}
?>
 

We usually don't like giving out full codes solutions to problems, but rather point people in the right direction so they can discover it themselves, but in this case I think the code is the best explanation.

[gater]

Ok. Assuming I am understanding you correctly, this code may be what you are looking for.

This is basically your code, using the modulus operator (%) to insert new rows after every third cell is printed. It will result in a 3 column table filled with images based on the values fetched from your database. No limit as to how many cells there are.

We usually don't like giving out full codes solutions to problems, but rather point people in the right direction so they can discover it themselves, but in this case I think the code is the best explanation.

THanks Atli! Works a charm.
Usually I don't ask for more than a snippet, but in this case after your edit of my sloppy code .... LOL I generally write Validated HTML and Css and will now try to improve my PHP as well.

Up to this point I have been more interested in just getting stuff to work!

Thanks again

[gater]

Hi Atli,
To help me understand the logic and syntax I am wondering if you could comment the following to describe the operators and functions?

# Print each cell
     $cellIndex = 0;
    while($row = mysql_fetch_assoc($result)) {
        # Add a new row if needed
        if($cellIndex % 3 == 0 and $cellIndex > 0) {
            echo "\n</tr>\n<tr>";
        }
        $cellIndex++;
 
        # Print the current cell
        echo "\n\t<td><img src=\"{$row['fdir']}/{$row['fname']}.{$row['f_ext']}\"></td>";
    }
 
    # Make sure the row is not missing cells
    while($cellIndex % 3 != 0) {
        echo "\n\t<td>&nbsp;</td>";
        $cellIndex++;
    }
 

THanks again

[Atli]

Sure, no problem.

<?php
#-
# The cell index is a zero-based index for
#  the cell currently being printed.
#  We use it to calculate when a new row has
#  to be printed
#-
$cellIndex = 0;
while($row = mysql_fetch_assoc($result)) {
    #-
    # The first of the two boolean checks in this
    #  if statement uses the Modulus operator to
    #  calculate if a new row is needed.
    #  The Modulus operator divides the $cellIndex
    #  by the number I specify (3) and returns the
    #  rest. So if the $cellIndex devided by 3 retuns
    #  a natural number (a number without a fraction)
    #  the calculation returns 0 and a new row is added.
    #  For example: 9 / 3 = 3.00 == 0 (no fraction)
    #               7 / 3 = 2.33 == 1 (fraction)
    #               6 / 3 = 2.00 == 0 (no fraction)
    # The later makes sure the index is higher than 0
    #  so we don't print an empty row at the top.
    #-
    if($cellIndex % 3 == 0 and $cellIndex > 0) {
        #-
        # Closes the row already opened when I printed
        #  the opening <table> tag, and opens a new one.
        #-
        echo "\n</tr>\n<tr>";
    }
    $cellIndex++;
 
    # Print the current cell
    echo "\n\t<td><img src=\"{$row['fdir']}/{$row['fname']}.{$row['f_ext']}\"></td>";
}
 
#-
# This is basically the same as the if statement above
#  except here, we are filling the last row with empty
#  cells to avoid rendering problems in the browsers.
#  The loop will run untill the $cellIndex of the current
#  cell would require a new row to be printed.
#-
while($cellIndex % 3 != 0) {
    echo "\n\t<td>&nbsp;</td>";
    $cellIndex++;
}
?>
 

Let me know if I missed something.

[gater]

Sure, no problem.

<?php
#-
# The cell index is a zero-based index for
#  the cell currently being printed.
#  We use it to calculate when a new row has
#  to be printed
#-
$cellIndex = 0;
while($row = mysql_fetch_assoc($result)) {
    #-
    # The first of the two boolean checks in this
    #  if statement uses the Modulus operator to
    #  calculate if a new row is needed.
    #  The Modulus operator divides the $cellIndex
    #  by the number I specify (3) and returns the
    #  rest. So if the $cellIndex devided by 3 retuns
    #  a natural number (a number without a fraction)
    #  the calculation returns 0 and a new row is added.
    #  For example: 9 / 3 = 3.00 == 0 (no fraction)
    #               7 / 3 = 2.33 == 1 (fraction)
    #               6 / 3 = 2.00 == 0 (no fraction)
    # The later makes sure the index is higher than 0
    #  so we don't print an empty row at the top.
    #-
    if($cellIndex % 3 == 0 and $cellIndex > 0) {
        #-
        # Closes the row already opened when I printed
        #  the opening <table> tag, and opens a new one.
        #-
        echo "\n</tr>\n<tr>";
    }
    $cellIndex++;
 
    # Print the current cell
    echo "\n\t<td><img src=\"{$row['fdir']}/{$row['fname']}.{$row['f_ext']}\"></td>";
}
 
#-
# This is basically the same as the if statement above
#  except here, we are filling the last row with empty
#  cells to avoid rendering problems in the browsers.
#  The loop will run untill the $cellIndex of the current
#  cell would require a new row to be printed.
#-
while($cellIndex % 3 != 0) {
    echo "\n\t<td>&nbsp;</td>";
    $cellIndex++;
}
?>
 

Let me know if I missed something.

That's terrific! THanks. I am assuming then that $cellIndex++; adds one cell to the current num ber of cells?

I appreciate your help very much. Many times I take a snippet and plug it in and then try to figure out why it works! Reverse-engineering makes the knowledge stick pretty well... but it is time consuming! LOL

[Atli]

That's terrific! THanks. I am assuming then that $cellIndex++; adds one cell to the current num ber of cells?

I appreciate your help very much. Many times I take a snippet and plug it in and then try to figure out why it works! Reverse-engineering makes the knowledge stick pretty well... but it is time consuming! LOL

You assume correctly, it does indeed add one to the cell index.

I'm glad I could help you out :)