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PHP

Posted by Logan R
Logan R
22,989 Points

Offsetting Json

Hey guys, I need a way to offset JSON.

Say I have posts.json:

{
    "posts": [
    {
        "id": "4"
    },
    {
        "id": "3"
    },
        {
        "id": "2"
    }
        ]
}

I want it so PHP will skip the { id 4 } and start with id 3. I tried array_shift() but it didn't work :/

If anyone could help, that would be great! I am trying to do pagination with static JSON soo yeah.

<?PHP
    $json_file = file_get_contents('data/posts.json');

    $json = json_decode($json_file, true);

    define('page', '2');

    $page = $json["posts"][0]["id"];

    //exit;
?>
<?PHP include 'inc/header.php'; ?>
    <section class="main">

    <?PHP
    $x=1;
    foreach($json["posts"] as $json) {
        if($x > page){
            break;
        }
        echo '
                $json["id"]
                ';
        $x=$x+1;
        }
    ?>

2 Answers

Logan R
Logan R
22,989 Points

I've solved the problem! I will post the code once I finish everything up :)

Edit - I feel super smart for this code, lol. I also had to do it all without help, so it's even better :D

<?PHP

    if(isset($_REQUEST['page'])){
        $page = intval($_REQUEST['page']);

        if($page < 1){
            $page = 1;
        }
    }else{
        $page = 1;
    }

    $json_file = file_get_contents('data/posts.json');

    $json = json_decode($json_file, true);

    define('page', '4');

    $pages = $json["posts"][0]["id"];

    $page_offset = $page*page-page;

?>
<?PHP include 'inc/header.php'; ?>
    <section class="main">

    <?PHP

    $x=$page_offset;

    $json = $json["posts"];

    for ($z=0; $z<page; $z++, $x++) {
        if($z > page){
            break;
        }
        if($x == $pages){
            break;
        }
        echo '
            <div class="post_block">
                <div class="feature">
                    <img src="'.$json["$x"]["img"].'">
                </div>
            </div>
        ';
    }
    ?>

{
    "posts": [
    {
        "id": "5",
        "img": "img/forest1.jpg"
    },
    {
        "id": "4",
        "img": "img/forest1.jpg"
    },
    {
        "id": "3",
        "img": "img/forest1.jpg"
    },
    {
        "id": "2",
        "img": "img/forest1.jpg"
    },
    {
        "id": "1",
        "img": "img/forest1.jpg"
    }
    ]
}
Mike Baxter
Mike Baxter
4,442 Points
Mike Baxter
Mike Baxter
4,442 Points

I'm not entirely sure, but here are a couple thoughts.

  1. Can't you just use numbers as your JSON id values instead of using strings? I guess it's trivial to do intval() on the string, but why do it if it's not necessary?

  2. My memory's a little fuzzy, but I don't think you'll want that comma at the end of your JSON array. (So do a logic check in the for loop to avoid inserting the comma at the end of the value the last time through the loop.)

Logan R
Logan R
22,989 Points
  1. There was a lot more to the file and I edited on the fly, I changed it in the official post.