trasfering value from php to javascript inconsistent

Question

my php code has a value of 2 digits like

 $var1 = 16; 
 $var2 = 24;
 $var3 = 31;

but when i used those value and put it in my javascript like for example

var var1 = <?php echo $var1; ?>
var var2 = <?php echo $var2; ?>
var var3 = <?php echo $var3; ?>
console.log(var1+"-"+var2+"-"+var3)

the output is **1-2-3** instead of **16-24-31** it only get the first digit i even put window.onloadfunction to make sure to load the php and html first before the script.

• Niccolò Campolungo: i even put window.onload function to make sure to load the php and html first before the script. <-- this is EPIC.
• Novocaine: If you view the source of the page, do the same (1-2-3) values show up in the var var1 = etc.. part of the code?
• George: 'to make sure to load the php and html first before the script' - PHP executes on the server, upon page request: always before the return javascript
• Bart: What source does it generate? Also, I can't imagine there would be * characters in your output.
• Elen: not clear from your snippet, but it looks like you are missing semicolons

Answer 1

The problem is a result of two things:

1. You are not ending your JS statements with semicolons.
2. PHP eats up one newline character if it follows the closing tag ?>.

This means that your JS code ends up being something like

var var1 = 16var var2 = 24var3 = 31

which is not what you expect (actually the above is a syntax error; if the code compiles in your case it might be a result of the example being not identical to the code that runs).

The proper solution is to terminate each statement with a semicolon:

var var1 = <?php echo $var1; ?>;
var var2 = <?php echo $var2; ?>;
var var3 = <?php echo $var3; ?>;

What would also work (although I recommend to avoid it) is to put some extra newlines after each assignment and let ASI take over:

var var1 = <?php echo $var1; ?>
var var2 = <?php echo $var2; ?>
var var3 = <?php echo $var3; ?>

As an aside, straight echo of the variables works in this case because they are numeric. In general, the proper way to transfer variables to JS is through json_encode:

var var1 = <?php echo json_encode($var1); ?>;

• DevfaR: this solve the problem as using json_encode to output the variable even if it has white spaces thank you for this
• Jon: @DevfaR: But your example variables don't contain whitespace. Why?

Answer 2

try this : It worked for me

<?php
 $var1 = 16; 
 $var2 = 24;
 $var3 = 31;
?>
<script>
var var1 = <?php echo $var1; ?>;
var var2 = <?php echo $var2; ?>;
var var3 = <?php echo $var3; ?>;
alert(var1+"-"+var2+"-"+var3);
console.log(var1+"-"+var2+"-"+var3);
</script>

• DevfaR: well it's the same problem i encounter