Why is the condition not returning after it met on php?-CodePudding

I came up with the following code:

<?php
if (block_rows('option') : while ( block_rows( 'option' ) ) : block_row( 'option' ); 
                                
    if ( !isset($id) ) { // meet only on the first iteration
        $a = 1; 
    }
    elseif ( isset($id) && $id == block_sub_value('ID') ) {
        $a  ;
    }
    elseif ( isset($id) && $id != block_sub_value('ID') ) {
        $a = 2;
    }

    $id = block_sub_value('ID');
?>

    <h1> Option - <?=$id;?> </h1> // prints only the ID
    <p> Sub Option - <?=$id . ' - ' . $a;?> <p> prints ID and the $a

<?php endwhile; endif;?>

The logic I'm trying to build is:

If is the first iteration of the loop, $a must be equal to 1. Period.
If $id and $a are equal, increase $a value by 1.
And finally, if $id and $a are different, $a must be equal to 2.

I have a list with some parent titles that has a $id number and child contents that has the parent $id number and also the $a number. Something like:

The point that don't seen to work well is actualy is the first condition. The very first $a starts with 2, not 1, almost like if after meeting the firts condition, the function continues to test the others, replacing the $a value.. I don't know why this happening.

CodePudding user response：

Once you started the while loop and passed the 1st iteration, isset($id) is true and so will not be reset to 1

Hence change the part:

<?php
if (block_rows('option') : while ( block_rows( 'option' ) ) : block_row( 'option' ); 
                                
    if ( !isset($id) ) { // meet only on the first iteration
        $a = 1; 
    }
// the rest of the code

to something like:

<?php

// set initial $oldid to be a value which is not possible
$oldid="-100";

if (block_rows('option') : while ( block_rows( 'option' ) ) : block_row( 'option' ); 
                                
    if ( $oldid !=$id ) { // meet only on the first iteration
        $oldid=$id;
        $a = 1; 
    }
// the rest of the code (please further amend if logically requires)

This is just one of the ways. Hope that it gives you some ideas