Javascript window.open两次调用

Question

I'm using this code in a php conditional if/else statement to open a new window.

echo("<script type=\"text/javascript\">
<!--
window.open(\"http://www.example.com/index.php?$var\");
//-->
</script>
");

It's opening 2 windows instead of one, but only on my live site (on a dedicated server) and not on the test site (shared server).

EDIT: From zebediah49's suggestion, I appended a random int variable after the new window url. It changes the variable with each new window instance, so I assume that means that it runs the conditional twice. I probably should mention that it's using Joomla and a 3rd-party community app, JomSocial.

Alright, as I was editing this and after ~5min of the same window being open, it opened a brand new instance of the window.open window. So obviously it automatically refreshes once as soon as it lands. I'll have to pry into that. Still any suggestions are welcome.

Thank you for your tips regarding language and best practices.

Answer 1

Since it's performing differently, there is either something different in the code between the two, or something different in the environment.

To test to be very, very, very sure that it is opening that specific url twice, have it append a random variable to the end of the URL:

$rando = rand();
window.open(\"http://www.example.com/index.php?$var&r=$rando\");

Also, if you want to avoid having quote issues, I would advise using HEREDOCs:

echo(<<<EOF<script type="text/javascript">
<!--
window.open("http://www.example.com/index.php?$var");
//-->
</script>
EOF
);

or with a variable

$content = <<<EOF<script type="text/javascript">
<!--
window.open("http://www.example.com/index.php?$var");
//-->
</script>
EOF;
echo($content);

I can't think of a good reason why that single line of JS would happen twice though, which is why I would want to see with the random var, such that there is no possible way other than that it could get opened twice. (If it was somewhere else in the file, it would not have the &r=...; if it was the same thing getting executed twice, &r=... will be different between the two)

Answer 2

First of all. Why those in your Javascript ? Those are XML Comment. You need to use /* ... */ or //

Did you mean

//<![CDATA[
...code...
//]]>

If this is the only call to window.open() your http://www.example.com/index.php might also make another window.open() call

Answer 3

可能是PHP回声被触发了两次？