Passing PHP array into JavaScript for loop

I am trying to pass some value from a PHP array into JavaScript.

My php variable $contacts_info has the followiing values.

Array ( [0] => Array ( [contact_id] => 20 [type_id] => 2 [contact_type] => Representative Phone [contact_value] => 0987654321 )
        [1] => Array ( [contact_id] => 21 [type_id] => 4 [contact_type] => Shop Address [contact_value] => 0987654321 ) 
        [2] => Array ( [contact_id] => 22 [type_id] => 3 [contact_type] => Emergency Phone [contact_value] => 0987654321 ) 
        [3] => Array ( [contact_id] => 23 [type_id] => 2 [contact_type] => Representative Phone [contact_value] => 0987654321 ) 
        [4] => Array ( [contact_id] => 24 [type_id] => 3 [contact_type] => Emergency Phone [contact_value] => 0987654321 ) 
        [5] => Array ( [contact_id] => 25 [type_id] => 4 [contact_type] => Shop Address [contact_value] => 0987654321 ) ) 1

I am trying to assign a specific value in some Combobox with a for loop using JavaScript. But I am having a problem doing so.

Type: ParseError

Message: syntax error, unexpected '<', expecting ']'

My JavaScript code:

<script>
    var total_counter = "<?php echo $total_contact; ?>";
    var contact_info = "<?php json_encode($contacts_info); ?>";
    for (var i = 0; i <= total_counter - 1; i++) {
        let element = document.getElementById("contact_type_id_" + i);
        element.value = "<?php echo $contacts_info[<script>document.writeln(i);</script>]['type_id'] ?>";
    }
</script>

The problem is in this part <?php echo $contacts_info[<script>document.writeln(i);</script>]['type_id'] ?>. Can anyone please help me with it.

Thank you.

Answer

Please do as follows,

1. You need to remove double quotes that enclose the PHP script, as "" treats it a string.

2. <?php echo json_encode($contacts_info); ?> was missing echo as JSON array wasn’t getting echoed such that it can be assigned to the javascript variable contact_info

3. The variable contact_info already have your JSON array, no need to again get it from PHP variable,

Eventually your code should look like,

 <script>
        var total_counter = <?php echo $total_contact; ?>;
        var contact_info = <?php echo json_encode($contacts_info); ?>;
        for (var i = 0; i <= total_counter - 1; i++) {
            let element = document.getElementById("contact_type_id_" + i);
            element.value = contact_info[i].type_id ;
        }
    </script>