php代码中的JavaScript脚本标记

Question

I have one page (parent) which opens a second page via popup (child)

On the second page I have the following PHP code which gets the value of an HTML element from the parent page:

 $var=print_r("<script type='text/javascript'>var x=window.opener.document.getElementsByName('name1');document.write(x[0].value)</script>",true);   

When I echo the variable $var I get exactly what I expect. Thus:

echo "test=" . $test;

... prints for example "Expenses" on the page.

So far so good.

The problem is when I try to write this variable to a file like:

$f=fopen("/mylog.txt","w+");
fwrite($f, $test);
fclose($f);

... then , instead of the actual value of $test (e.g. Expenses),

I get the whole script tag in my logfile, thus:

<script type='text/javascript'>var x=window.opener.document.getElementsByName('name1');document.write(x[0].value)</script>

Assuming that print_r with 'true' parameter returns the value to my $test variable, why is it writing the exact script tag to the logfile?

How can I overcome this?

Answer 1

When you echo the value to a browser, it will run the JavaScript and display the result.

When you save it to a file, the JavaScript isn't executed.

In both cases, the full script is output, but the browser is actually running the script, whereas your text editor won't.