I don't understand why replace() function doesn't work into my jQuery function:
jQuery(document).ready(function($){
var amount_min = <?php if($_GET['amount_min']) echo $_GET['amount_min']; else echo '0'; ?>;
var amount_min = amount_min.replace(/[^\d]/g, "");
$('input[name=amount]').val(amount_min);
});
Whatever input I give (for example "100ab" or "10.000") it doesn't replace it with "100" or "10000". How to do?
You forgot to put double-quotes.
var amount_min = "<?php if($_GET['amount_min']) echo $_GET['amount_min']; else echo 0; ?>";
Because, replace works in Strings.
If for any religious reason you don't want to wrap the PHP in double quotes then output them along with the number.
var amount_min = <?php echo '"' . ($_GET['amount_min'] ? $_GET['amount_min'] : 0) . '"'; ?>;
Compulsory validation you can use:
var amount_min = <?php echo '"' . (int)($_GET['amount_min']) . '"'; ?>;
<?php and ?>
can you please try this:
$(document).ready(function(){
var amount_min = "<?php if($_GET['amount_min']){ echo $_GET['amount_min'];}else{ echo '0';} ?>";
console.log("original-> "+amount_min);
var amount_min = amount_min.replace(/\D/g,'');
console.log("replaced-> "+amount_min);
});
Your PHP code is outputting a number:
var amount_min = 100;
Since you're expecting a string, wrap it in quotes:
var amount_min = "<?php if($_GET['amount_min']) echo $_GET['amount_min']; else echo '0'; ?>";
I haven't touched PHP in years, but I think you could simplify your code a little:
var amount_min = "<?php echo($_GET['amount_min'] || '0'); ?>";
Also, why don't you just fetch the GET parameter with JavaScript?
You don't need the .replace() code (it also only works on strings); PHP can already do the proper conversion for you:
$(function() {
var amount_min = <?php echo isset($_GET['amount_min']) ? (int)$_GET['amount_min'] : 0; ?>;
$('input[name=amount]').val(amount_min);
});
You could also use filtering for this:
<?php echo filter_input(INPUT_GET, 'amount_min', FILTER_VALIDATE_INT, array('options' => array('default' => 0))); ?>
Note that filter_input would not accept a value like 100abc, so use wisely.
If you still want to use strings safely in JavaScript you should use json_encode().
Btw, any answer that involves an unmodified echo of a request variable from PHP inside JavaScript code is wrong and can cause XSS attacks! You have been warned.
Update
The regular expression based replacement can also be done in PHP:
var amount_min = <?php echo (int)preg_replace('/\D+/', '', isset($_GET['amount_min']) ? $_GET['amount_min'] : 0); ?>;
Since all non-digits are removed, you can safely apply the (int) cast.
.replace()function for numbers in JavaScript.