pass php value to html element without using echo - php

Question

I am getting a value with php $_GET[], and I want to pass it as the value of a simple html input element. I know I can do it like this:
<?
$value = $_GET['value'];
echo '<input type="text" name="value" value="'.$value.'" />';
?>
But is there any way to separate the php from html, giving the value to the textbox without echoing it?
I would like to create the textbox as regular html element, and only use php in the part where I set its value.
The answer of Iaroel was more practical for my purposes, but I liked the way that the accepted answer covered many concerns - I think it will be more valuable to other users.

Answer 1

You don't want an error when the $_GET['value'] becomes undefined.
<?php
$value = isset($_GET['value'] ? $_GET['value'] : '');
?>
<input type="text" name="value" value="<?php echo $value; ?>">
But be mindful with malicious data that can be inserted in $_GET['value'] so you've got to apply proper sanitation to $value
With regards to "Getting $_GET['value'] without PHP"
You can get it without PHP script by creating a small javascript function:
<script type="text/javascript">
function $_GET(q,s) {
s = s ? s : window.location.search;
var re = new RegExp('&'+q+'(?:=([^&]*))?(?=&|$)','i');
return (s=s.replace(/^?/,'&').match(re)) ? (typeof s[1] == 'undefined' ? '' : decodeURIComponent(s[1])) : undefined;
}
</script>
What the hell was that regular expression? It's just a matter of matching pattern from the URL.
Now, you can use this $_GET() method to assign the value to that textbox. In this example, I used jQuery:
<script type="text/javascript">
$(document).ready(function() {
$('input[name="value"]').attr('value', $_GET('value'));
});
</script>
Now your HTML code will be as simple as this:
<input type="text" name="value">
Reference: http://www.onlineaspect.com/2009/06/10/reading-get-variables-with-javascript/

Answer 2

If you don't wish to echo anything inside HTML, use Ajax call to get values.
$.ajax({
url: 'getValues.php',
type: 'post',
dataType: 'json',
success: function (json) {
if (json) {
$.each(json, function (k, v) {
$(k).val(v);
});
}
}
});
[PHP]
echo json_encode(array('#first_input_id' => 'val1', '#second_input_id' => 'val2', '.some_classes' => 'val5'));
Or if values are static, you can use local json file.

Answer 3

Do you mean like this?
<?php
$value = $_GET['value'];
?>
<input type="text" name="value" value="<?php echo $value;?>" />
Or this (not advised):
<?php
$value = $_GET['value'];
?>
<input type="text" name="value" value="<?= $someVar ?>" />
But i would suggest looking into a template engine for example http://www.smarty.net/

Answer 4

If your php configuration allows short tags you can do this:
<input type="text" name="value" value="<?=$_GET['value'];?>" />

Answer 5

you can try without echo
<?php $value = $_GET['value'];?>
<input type = "text" name = "value" value="<?= $value; ?>" />

Answer 6

If its really important for your project, ideally you want to separate your php code from your html tags. this can achieve by using some template engine.
There are some well known options available, best if you check and see which one suites your use-case best.
Mustache
Smarty
and of course Twig

Answer 7

You can use PHP Heardoc option. find the link here.
http://www.hackingwithphp.com/2/6/3/heredoc