(PHP 5 >= 5.3.0, PHP 7, PHP 8)
What's the worse thing that could happen if you use goto (xkcd URL)? » xkcd
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
<?phpgoto a;echo 'Foo';a:echo 'Bar';?>
The above example will output:
Bar
Example #2 goto
loop example
<?phpfor ($i = 0, $j = 50; $i < 100; $i++) { while ($j--) { if ($j == 17) { goto end; } }}echo "i = $i";end:echo 'j hit 17';?>
The above example will output:
j hit 17
Example #3 This will not work
<?phpgoto loop;for ($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