通过使用JavaScript变量作为索引来访问PHP数组元素

Question

The code looks like this:

PHP file

<?php
...
$arrayName = ['ArrayValue_0', ..., 'ArrayValue_n'];
...
php?>

JavaScript

$('.elementClass').each(function(index, id) {
    $(id).html('<?php echo $arrayName[index - 1]?>');
});

But you can't just insert a JavaScript variable like that into php tags so index is never received. I know this can be done via AJAX but is there any other way? Thanks in advance.

Additional info: I've been told to do this in PHP so there's no posibility of switching the array to a JS file.

Answer 1

You can define arrayName variable in JS and initialize it with the value from the server:

var arrayName = <?php echo json_encode($arrayName); ?>;
$(".elementClass").each(function(index, id) {
    $(id).html(arrayName[index-1]);
});

Answer 2

What you're trying to do will not work. For example this:

$(id).html('<?php echo $arrayName[index - 1]?>');

The above will never, ever work, because PHP is run on a server , not on your user's browser.

What you need to do is send the variable somehow to the server. You have a plethora of options:

1. Use a form and read a $_POST variable
2. Append it to a URL and read a $_GET variable
3. Use AJAX and asynchronously send that variable to the server
4. Return the whole array from PHP to your Javascript code
5. etc. etc.

Remember, PHP runs on the server, which renders the page, which then in turn is read by your browser where you run Javascript. You can't paste PHP code into the page and expect it to be parsed by PHP!

Answer 3

如果您希望从服务器获取信息（PhP在服务器上运行），则需要返回服务器，因此在加载包含PhP数组完整内容的页面时，您可以即时创建javascript变量，或者您可以使用ajax返回服务器，而无需刷新整个页面。