Sending variables in URLs in PHP with echo

问题:

I can't really find good guidelines through Google searches of the proper way to escape variables in URLs. Basically I am printing out a bunch of results from a MySQL query in a table, and I want one of the entries in each row to be a link to that result's page. I think this is easy, that I'm just missing a apostrophe or backslash somewhere, but I can't figure it out. Here's the line that's causing the error:

echo "<a href = \"movies.php/?movie_id='$row['movie_id']'\"> Who Owns It? </a> ";

and this is the error I'm getting:

Parse error: syntax error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING

How do I fix this error?

In addition, what are some general guidelines for working with echo and variables in URLs?

回答1:

echo "<a href = \"movies.php/?movie_id='$row['movie_id']'\"> Who Owns It? </a> ";

There are two things here that should be changed. For one thing there shouldn't be a / after movies.php. The second is that there aren't any apostrophies around url variables. It should be movie_id=$row['movie_id']. Whenever I use a php variable I usually concatonate it instead of embed it in the quotations. So in the end I'd do something like this:

echo "<a href=\"movies.php?movie_id=" . $row['movie_id'] . "\"> Who Owns It? </a>";

回答2:

The $row['movie_id'] inside the double quoted string is not allowed (especially the single quotes). Either write it without ' or use the curly braces syntax:

echo "<a href = \"movies.php/?movie_id='$row[movie_id]'\"> Who Owns It? </a> ";
echo "<a href = \"movies.php/?movie_id='{$row['movie_id']}'\"> Who Owns It? </a> ";

See variable parsing for further information.

回答3:

This is a better way:

$movie_id = urlencode($row["movie_id"]);
echo '<a href="movies.php/?movie_id=', $movie_id, '"> Who Owns It? </a> ';

Good luck!

回答4:

This is a better(er) way:

$movie_id = urlencode($row["movie_id"]);
echo "<a href=\"movies.php?movie_id={$movie_id}\"> Who Owns It? </a> ";

Easier to read. Besides the single and double quote speed thing is not much of an issue any more.

回答5:

Echo or URLs have nothing to do with your problem. It's PHP strings syntax.