How to correctly print the repeated rows? - php

Question

I have simulated the mysql result from an old SO question as the following array:
<?php
$arr = array(
array(
'title'=>'Test',
'name'=>'ABC',
'cat_desc'=>'ABC_DESC',
'parent'=>0,
'parent_menu'=>1
),
array(
'title'=>'Test2',
'name'=>'DEF',
'cat_desc'=>'DEF_DESC',
'parent'=>0,
'parent_menu'=>2
),
array(
'title'=>'Test2',
'name'=>'GHI',
'cat_desc'=>'GHI_DESC',
'parent'=>1,
'parent_menu'=>0
),
array(
'title'=>null,
'name'=>'JKL',
'cat_desc'=>'JKL_DESC',
'parent'=>2,
'parent_menu'=>0
)
);
//print_r($arr);
?>
Now I wonder if I could print the result in this format:
<table>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
<tr>
<td> Menu Title Test </td>
<td> Main Category ABC</td>
</tr>
<tr>
<td>GHI</td>
<td>GHI_DESC</td>
</tr>
<tr>
<td> Menu Title Test2 </td>
<td> Main Category DEF</td>
</tr>
<tr>
<td>JKL</td>
<td>JKL_DESC</td>
</tr>
</table>
I am trying the following php to print but it could not give the expected result:
<table>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
<?php
$r = 0;
while(list($key, $val)=each($arr)) {
if($val['parent']==0):
if($r % 1==0): ?>
<tr>
<td> Menu Title <?php echo $val['title'];?> </td>
<td> Main Category <?php echo $val['name'];?></td>
</tr>
<?php endif;
endif;
if($val['parent']!=0){ ?>
<tr>
<td><?php echo $val['name'];?></td>
<td><?php echo $val['cat_desc'];?></td>
</tr>
<?php
}
$r++;
} ?>
</table>
Your help and suggestion is very much welcome.

Answer 1

I find it difficult to figure out what you exactly want from your array structure. But I noticed that array element 0 is paired with element 2, and element 1 is paired with element 3. Therefore my code would be like following. It will give you exactly the table that you wanted.
print "<table border=1>";
$numArray = count($arr) / 2;
for($i=0;$i<$numArray;$i++) {
$element = $arr[$i];
print "<tr><td>Menu Title {$element['title']}</td><td>Main Category {$element['name']}</td></tr>";
$element = $arr[$i+2];
print "<tr><td>{$element['name']}</td><td>{$element['cat_desc']} </td></tr>";
}
print "</table>";

Answer 2

You can use this where I commented what to do and why
<table>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
<?php
// Store the array into temporary array
$temp_array = $arr;
foreach ($arr as $akey => $sArr)
{
// Check that prrent is 0
if ( $sArr['parent'] ==0 )
{
// Store parent_menu id
$parent_menu = $sArr['parent_menu'];
?>
<tr>
<td> Menu Title <?php echo $sArr['title'];?> </td>
<td> Main Category <?php echo $sArr['name'];?></td>
</tr>
<?php
// Unset or remove current index from array
unset($temp_array[$akey]);
// Iterate all rows
foreach ($temp_array as $skey => $aval)
{
// Check that it has parent for the current menu
if ( $aval['parent'] == $parent_menu )
{
?>
<tr>
<td><?php echo $aval['name'];?></td>
<td><?php echo $aval['cat_desc'];?></td>
</tr>
<?php
}
}
// End of foreach
}
// End of if
}
// End of foreach
?>
</table>

Answer 3

I find that data from a relational DB doesn't really lend itself to direct use and requires some massaging to lower the code complexity. So, if your aim is to make a dynamic menu with submenus, I would suggest refactoring the data structure into more of a tree structure and then looping over each level.
A better data structure would be:
$menus = array(
1 => array( // original array item index 0
'title'=>'Test',
'name'=>'ABC',
'cat_desc'=>'ABC_DESC',
'parent'=>0,
'parent_menu'=>1
'children'=> array( // new array containing submenus
array( // original array item index 2
'title'=>'Test2',
'name'=>'GHI',
'cat_desc'=>'GHI_DESC',
'parent'=>1,
'parent_menu'=>0
),
),
),
2 => array( // original array item index 1
'title'=>'Test2',
'name'=>'DEF',
'cat_desc'=>'DEF_DESC',
'parent'=>0,
'parent_menu'=>2
'children'=> array( // array containing original item index 2
array(
'title'=>null,
'name'=>'JKL',
'cat_desc'=>'JKL_DESC',
'parent'=>2,
'parent_menu'=>0
),
),
),
);
Rather than just entering the data in this more covenient form, it is good practice to convert it. So, to get from the original data to this structure you can use a simple single pass foreach loop:
$menus = [];
foreach($arr as $item) {
if($item['parent'] == 0) {
$item['children'] = array();
$menus[$item['parent_menu']] = $item;
}
else {
$menus[$item['parent']]['children'][] = $item;
}
}
Once you have the data in a nice convenient form you can use simple nested foreach loops to iterate it and output the table in a clear manner like this:
<table>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
<?php foreach($menus as $menu) { ?>
<tr>
<td> Menu Title <?php echo $menu['title'];?> </td>
<td> Main Category <?php echo $menu['name'];?></td>
</tr>
<?php foreach($menu['children'] as $child) { ?>
<tr>
<td><?php echo $child['name'];?></td>
<td><?php echo $child['cat_desc'];?></td>
</tr>
<?php } } ?>
</table>

Answer 4

From what I see, I believe $r % 2 makes a little more sense than $r % 1
In case $r is an integer, $r % 1 will always return a zero. Looks like in your case you use this to split logic for odd and even numbers, which makes sense for your data set.
Make sure the data set doesn't change. Maybe it'd be better use a more reliable approach. Adding indexes to the data set wouldn't harm either :)