这句if正确得怎么写？

if ($_GET['lx'] == "1"): <br />$file_name = $r['titlepic'];<br />else:<br />$file_name = $r['picurl'];<br />endif;

if..endif syntax<br />The `alternative' way to write if/elseif/else statements, using if(); elseif(); else; endif; cannot be efficiently implemented without adding a large amount of complexity to the 3.0 parser. Because of this, the syntax has been changed: Example E-5. Migration: old if..endif syntax<br /><br />if ($foo);<br />    echo "yep\n";<br />elseif ($bar);<br />    echo "almost\n";<br />else;<br />    echo "nope\n";<br />endif;  <br /> <br />Example E-6. Migration: new if..endif syntax<br /><br />if ($foo):<br />    echo "yep\n";<br />elseif ($bar):<br />    echo "almost\n";<br />else:<br />    echo "nope\n";<br />endif;  <br /> <br />Notice that the semicolons have been replaced by colons in all statements but the one terminating the expression (endif). <br /><br />