Javascript and php interaction to go through an array

Question

Possible Duplicate:
Reference: Why does the PHP code in my Javascript not work?

This is my attempt to go through an array of pictures.

$rows2 is an array of pictures. I can manually

     echo '<img src="' . $rows2[0] . '"/>';

or

     echo '<img src="' . $rows2[1] . '"/>';

or

     echo '<img src="' . $rows2[2] . '"/>';

and that works fine. So, I added a javascript button and an alert button for testing.

I can see that the var is change from 0 to 1 to 2 however, no picture appears at any point.

<div class="half" id="right">
<?
     echo '<img src="' . $rows2["<script>document.write(counter)</script>"] . '"/>';


?>
<button onclick="counter++">Increment</button>
<button onclick="counter--">Decrement</button>
<button onclick="alert(counter)">alert</button>

</div>

what am I doing wrong?

do `$rows2` contain the file extension in each index? (.gif, .jpeg, .png etc) — Sterling Archer, Dec 19 '12 at 00:39
its a blob. so, technically now, however, like i said, manually putting 0, 1, 2, or 3 will work. — Cripto, Dec 19 '12 at 00:40
`$rows2[""]`? You do know the php will execute before any javascript. — Musa, Dec 19 '12 at 00:41
What do you mean by a blob? Why don't you just iterate the array or do you have to do it this way? — Sterling Archer, Dec 19 '12 at 00:42
See the question linked as a possible duplicate. It's not an actual duplicate, but the answer there will explain the problem. You can't mix php an js like that, php runs *before* js. — bfavaretto, Dec 19 '12 at 00:42

score 2 · Accepted Answer · answered Dec 19 '12 at 00:44

2

I think you have a misunderstanding about how Javascript and PHP interact. Your PHP will be run and sent to the client. The clients browser will recieve this:

<div class="half" id="right">
<img src=""/>
<button onclick="counter++">Increment</button>
<button onclick="counter--">Decrement</button>
<button onclick="alert(counter)">alert</button>
</div>

Note that src is empty because (presumably) $rows2 doesn't have a value with key <script>document.write(counter)</script>

You'll have to rework the code so that the Javascript already has all the information it needs (i.e. by writing an array of images into the javascript).

answered Dec 19 '12 at 00:44

Jim

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If I understand correctly, hand off all of the echo ''; into an array in JS and have it write out the entire thing? in side my php tags? – Cripto Dec 19 '12 at 17:50
@user1048138 Pretty much. Then the js will have an array of image sources so when the button is clicked the js can grab the next source and update the image src. – Jim Dec 19 '12 at 19:46

Javascript and php interaction to go through an array

1 Answers1