You should mention the label can't be a variable
(PHP 5 >= 5.3.0, PHP 7, PHP 8)
The goto
operator can be used to jump to another
section in the program. The target point is specified by a case-sensitive label
followed by a colon, and the instruction is given as
goto
followed by the desired target label. This
is not a full unrestricted goto
. The target
label must be within the same file and context, meaning that you cannot jump
out of a function or method, nor can you jump into one. You also
cannot jump into any sort of loop or switch structure. You may jump
out of these, and a common use is to use a goto
in place of a multi-level break
.
Example #1 goto
example
<?php
goto a;
echo 'Foo';
a:
echo 'Bar';
?>
The above example will output:
Bar
Example #2 goto
loop example
<?php
for ($i = 0, $j = 50; $i < 100; $i++) {
while ($j--) {
if ($j == 17) {
goto end;
}
}
}
echo "i = $i";
end:
echo 'j hit 17';
?>
The above example will output:
j hit 17
Example #3 This will not work
<?php
goto loop;
for ($i = 0, $j = 50; $i < 100; $i++) {
while ($j--) {
loop:
}
}
echo "$i = $i";
?>
The above example will output:
Fatal error: 'goto' into loop or switch statement is disallowed in script on line 2
// goto is STILL a good feature if you know how to use it.
// Just don't use it in loops.
// Example:
$sql = "DELETE FROM sometable WHERE id=?;";
$stmt = $conn->prepare($sql);
if (!$stmt) {
echo "ERR prepare_fail";
goto End;
}
$bind = $stmt->bind_param('i', $id);
if (!$bind) {
echo "ERR bind_fail";
goto End;
}
$exec = $stmt->execute();
if (!$exec) {
echo "ERR exec_fail";
goto End;
}
if (isset($_POST['file'])) {
$file = "../" . $_POST['file'];
if (is_file($file)) { unlink($file); }
}
echo "OK delete_success" ;
End:
$stmt->close();
$conn->close();
exit;
/*
instead of repeating the $stmt->close() and $conn->close(),
we save a few lines by adding a goto and just close everything at the end.
*/
$array = array();
for ($i = 0; $i <= 10; (int)$array[] = $i, $i++);
var_dump($array );
$countarray = (count($array) - 2) ;
var_dump($countarray);
static $goto = 0;
/***************************************************************************************************/
b:
$array[$goto] = $array[$goto] * 2;
if ($goto <= $countarray){
$goto++;
goto b;
}else{
goto a;}
a:
/***************************************************************************************************/
var_dump($array);