pass associative array from php to javascript

Question

Possible Duplicate:
How to pass an array of strings from PHP to Javascript using $.ajax()?

I want to pass a associative array from php code to javascript code. Please help me. how do I do this ? Is JSON helpful in this matter? If yes then please provide a simple code for help. Thank you.

From comment below:
HTML + PHP code

<td> 
    <input type="text" style="width:70;" name="<?php echo $quantity;?>" id="<?php echo $quantity;?>" onkeyup="check_valid_range('<?php echo $itemName;?>','<?php echo $quantity;?>',<?php echo json_encode($product_inventory);?>);">
</td> 
<script type="text/javascript"> 
    function check_valid_range(product_field, quantity_field, inventory){ 
        var product = document.getElementById(product_field).value; 
        var quantity = document.getElementById(quantity_field).value; 
        var v = inventory[product]; 
        alert(v); 
    } 
</script>

Solution

JSON is perfect:

<?php

$mySweetJSONString = json_encode($myAssocPHPArray);

?>
<script>
    var iWantThePHPArrayHere = <?php echo $mySweetJSONString; ?>;
</script>

User pst brought up these concerns:

• "array("</script>") -- darn, just broke this "perfect" approach."
  It seems to work because (</script> => <\/script>):
  jsFiddle

• "What about ]]> which could occur in XHTML?"
  The string is able to be transferred.
  jsFiddle

---

Update:

In regards to debugging the problem with the JS:
Are there any errors in the console? One of your document.getElementById(...) might be returning a null. Therefore the member value doesn't exist.

Comments

[Admin]

Done research much? This is actually a somewhat common task (however, converting to JSON is not technically enough, "</script>" appearing in the JSON is a counter-example. JSON "works" simply because it is a proper subset of Javascript Literal Notation.

[Paweł Adamski]

Why all the downvotes? This is not a terrible question.

[Joe the Person]

Think its because its a Duplicate.

[cdhowie]

That a duplicate question exists is not a valid reason to downvote. You downvote because a question is difficult to understand or poorly-worded, not because someone else asked the same thing already.

[Gordon]

@cdhowie If you hover over the downvote button you will see that it says: "this question does not show any research effort". Given that there is almost 4k results in the linked search above and there is multiple duplicates, this clearly warrants a dv. There should be even more results on Google for that. This question does not deserve any upvotes.

[afuzzyllama]

What is the value of alert(v)?

[Abhimanyu1310]

function is not working. no output. I think this is because calling of the function is wrong. But I dont know what is wrong

[Abhimanyu1310]

@Gordon I have Google enough. I asked this question because I am passing the array using a function and the function is not working.

[afuzzyllama]

@Abhimanyu1310 - are there any errors in the console? One of your document.getElementById(...).value might be returning null.

[Arnaud Le Blanc]

@pst this is wrong, JSON allows to escape the / character for the purpose of escaping </script>, and json_encode does it. stackoverflow.com/questions/7217054/…

[Abhimanyu1310]

If I dont use json_encode($arrayname) then it works perfectly. But when I pass the array it doesn't. And no error on console.

[afuzzyllama]

Please post your JSON string from your array.

[afuzzyllama]

Thanks @cdhowie, I usually try to have complete code O_o

[cdhowie]

No problem, just trying to make the code clearer. :) +1 too, this is the right approach.

[Admin]

This is not very happy when "</script>" appears in the JSON. While JSON is a subset of JavaScript literals, not all JavaScript literals are valid in a <script> element (and I'm ignoring XHMTL entirely). I really wish there was a function designed just to facilitate this particular use-case with it's little caveats.

[Abhimanyu1310]

I am doing the same thing. json_encode function. But with a small difference, I am passing array of php to js by calling a function. And the function is not working. I just used alert() in the calling funcition to check if value is received. But nothing happened.

[afuzzyllama]

Why would '</script>' appear in the JSON? I don't understand your comment

[afuzzyllama]

@Abhimanyu1310 - Please post your code, I cannot debug code I cannot see

[Abhimanyu1310]

code<script type="text/javascript"> function check_valid_range(product_field, quantity_field, inventory) { var product = document.getElementById(product_field).value; var quantity = document.getElementById(quantity_field).value; var v = inventory[product]; alert(v); } </script> code <input type="text" style="width:70;" name="<?php echo $quantity;?>" id="<?php echo $quantity;?>" onkeyup="check_valid_range('<?php echo $itemName;?>','<?php echo $quantity;?>',<?php echo json_encode($product_inventory);?>);">

[Abhimanyu1310]

sorry I dont know how to post the code more clearly. New on Stackoverflow.

[Abhimanyu1310]

code <script type="text/javascript"> function check_valid_range(product_field, quantity_field, inventory) { var product = document.getElementById(product_field).value; var quantity = document.getElementById(quantity_field).value; var v = inventory[product]; alert(v); } </script>

[afuzzyllama]

post it in your question

[Arnaud Le Blanc]

This is perfectly safe, even if the string contains </script>. PHP's json_encode escapes the / for this purpose.

[Admin]

@arnaud576875 Corrected downvote. What about ]]> which could occur in XHTML?

[Arnaud Le Blanc]

That may (assuming that the document is really parsed as XML) close the CDATA node, not the script element. That may cause a XML syntax error if the document is parsed as XML (nobody send an xml content-type).