Question

I am having a problem with this code:

$myvariable = "<?php $user_id = '5'; ?>";

…now I then write it to file using php…

and this is what I see when I open the saved file:

<?php  = '5'; ?>

$user_id is missing!

Why is this happening and is there a way to fix this problem?

Answer 1

When you use double-quotes, any $variables in the text will be replaced with their current value. Because $user_id isn’t defined in the code that’s currently running, it’s replaced with nothing.

There are a couple of ways to prevent this from happening. You could wrap your string in single-quotes instead, escaping the existing single-quotes in the text with a backslash:

$myvariable = '<?php $user_id = \'5\'; ?>';

Or you cou could instead escape the $ with a backslash, so that it’s not interpreted:

$myvariable = "<?php \$user_id = '5'; ?>";