How to bring PHP array value to Javascript?

Question

<html>
<head>
<script language="javascript">
    function validatefrm(){

        for (var i= 0 ; i< 3 ; i++){

        window.alert(i+window.document.contact[i].value); 
        }

        return false; //to prevent form from submitting for debugging
    }
</script>
</head>
<body>
<form name="editform" onsubmit="return validatefrm();" method="POST">
<?php

for($i=0; $i<3; $i++){
    print "<input type='textbox' id='contact".$i."' value='".$i."'>";
}
?>
<input type="submit" value="Submit Values">
</form>
</body>
</html>

Hi, I'm new to php and javascript. I'm trying to call the form with the value of 0,1,2 with javascript but it wont work. Unless i delete the for loop in javascript function and hard code it as Window.alert (window.document.contact0.value) and so on....Anyone can help? Must appreciate.

From the title, it made me feel its a duplicate of a question I answered. But it seems its not, can be a little more specific what you want, and where its failing? — UltraInstinct
– UltraInstinct, Commented Nov 24, 2013 at 18:46
Hi, ya i got read through your post. But i think mine is different, i'm trying to get 3 input from the form like 0,1,2 as the value...then once submit button is click...the window alert should also print out value that i have store in the form such as 0,1,2 — Marcus
– Marcus, Commented Nov 24, 2013 at 18:50
Yes, I understood you question after I posted that comment. And I have answered below. HTH — UltraInstinct
– UltraInstinct, Commented Nov 24, 2013 at 18:52

UltraInstinct · Accepted Answer · 2013-11-24 18:48:00Z

1

If I get your question correctly, you need to access the elements by ID. And the correct way is to use document.getElementById(...). In your case:

for (var i= 0 ; i< 3 ; i++){
    window.alert(document.getElementById('contact' +i).value); 
}

answered Nov 24, 2013 at 18:48

UltraInstinct

44.6k12 gold badges85 silver badges108 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Marcus Over a year ago

Sorry for any inconvenient.

UltraInstinct Over a year ago

No problem, glad I was able to help :-)

charlietfl · Accepted Answer · 2013-11-24 18:49:06Z

1

You are setting an ID for each element with php contact0, contact1 etc.

So in javascript look for that ID

function validatefrm(){

    for (var i= 0 ; i< 3 ; i++){
        window.alert(i+ ' '+ document.getElementById('contact'+i).value); 
    }
    return false; //to prevent form from submitting for debugging
}

answered Nov 24, 2013 at 18:49

charlietfl

172k14 gold badges125 silver badges154 bronze badges

Comments

Dan · Accepted Answer · 2013-11-24 18:55:40Z

0

Your best choice would most likely be to use json_encode. This method outputs the array as a JSON array which can be assigned to a JavaScript variable in <script> tags. Associative arrays on the PHP side would get converted into JSON objects.

json_encode in the PHP documentation

<?php
$myArr = array(0, 1, 2);
?>

<!-- somewhere in the HTML document -->
<script>
   var myArr = <?php echo json_encode($myArr); ?>;
   // do something with myArr
   console.log(myArr);
</script>

answered Nov 24, 2013 at 18:55

Dan

5,0804 gold badges37 silver badges51 bronze badges

Comments

Krease · Accepted Answer · 2013-11-24 18:59:50Z

0

The php is executed on the server side, before it makes it to the browser. The javascript is executed on the client side, in the browser. You cannot pass php values to javascript like this.

You can make the php output javascript (in a script tag), and use that in your javascript code though.

<script>
  var foo = [];
  <?php
    for($i=0; $i<3; $i++){
      print "foo[".$i."] = ".$i;
    }
  ?>
console.log(foo[0] + ", " + foo[1] + ", " + foo[2]);
<script>

edited Nov 24, 2013 at 18:59

answered Nov 24, 2013 at 18:44

Krease

16.3k8 gold badges58 silver badges92 bronze badges

1 Comment

UltraInstinct Over a year ago

I think his question is completely different. He wants to know why his for loop in javascript isn't working.

Collectives™ on Stack Overflow

How to bring PHP array value to Javascript?

4 Answers 4

2 Comments

Comments

Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

2 Comments

Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related