PHP循环的每个第3次迭代

Question

When I say 'Every 3rd Iteration' I mean 'Every 3rd Iteration... starting from number 4'

If it were just every 3rd, I would target the appropriate iterations like so:

<?php if ($count % 3 == 0) : ?>

Bear in mind I've set $count to 1 beforehand

But the iterations need to start with the 4th, then 7th, 10th etc.

Does anyone know how I can acheive this? Can I do it with a simple if statement like the one above?

Unfortunately I don't think a for loop will be possible as this is a WordPress loop I'm dealing with

Answer 1

Your thoughts about using the modulus operator are sound, you just need to expand the scope of your logic surrounding it:

You want every third iteration after the initial 4 have passed. Begin your logic after the first 4:

if ($count > 4)

Then, you want each 3 after that. Your counter includes the initial 4 iterations you didn't want to include, so remove that from your counter and check if the current iteration is a multiple of 3:

if (($count - 4) % 3 === 0)

This should give you what you're looking for.

if ($count > 4)
{
    if (($count - 4) % 3 === 0)
    {
        ...
    }
}

You can also put this into one line:

if ($count > 4 && ($count - 4) % 3 === 0)
{
    ...
}

Answer 2

foreach($array as $key=>$value){
    if($key % 3 != 0){
        continue;
    }
}