On Tue, 2010-04-13 at 12:04 -0400, steve_r wrote:
> I'm new to programming, drive a truck in the day, now taking night courses
> to get a better job for my family. Please bear with me if this is a dumb
> question, I don't have much experience.
>
> I'm taking a night class in HTML and PHP and can't figure out a problem and
> can't find the answer in the book for the course ("Beginning PHP5" by Wrox
> Press), on the switch manual page on php.net, or in any postings to this
> mailing list.
>
> I'm trying to pass a value to a simple integer to a function, and then use
> that value in a switch statement. The problem I'm having is that regardless
> of the value of 'val', the first case statement always executes. Even if I
> put '$val = 0' right before the case statement, the first case statement
> executes. The syntax looks correct based on the php.net man page for switch
> and from the user examples. It also matches the example in the book.
>
> function check_it2($val) {
> echo gettype($val);
> switch($val) {
> case($val > 0 ):
> echo "Switch greater than 0";
> $diff_obj = 1;
> break;
> case($val < 0 ):
> echo "Less than 0";
> $diff_obj = -1;
> break;
> default:
> echo "Equal to 0";
> $diff_obj = 0;
> }
> print("Here's \$diff_obj2 in the function: " . $diff_obj);
> return $diff_obj;
> }
>
> I even put the following code before the switch statement just to make sure
> I'm not crazy:
>
> $val = 0;
> if($val > 0) {
> echo "If greater than 0";
> }
> else {
> echo "If not greater than 0";
> }
>
> and it falls through to the else as it should.
>
> I've tried putting single and double quotes around the case variables but it
> always prints out the first value. I've recoded to use a series of if
> statements but why isn't the switch working? I've read through the 'loose
> comparison' section, but nothing appears to apply there.
>
> Sorry for the basic question.
>
> Steve Reilly
Change the first line of the switch to
switch(true)
and it will be functioning as you want. Normally, a switch has this
form:
switch($val)
{
case 1:
{
// statements
break;
}
case 10:
{
// statements
break;
}
default:
{
// statements
}
}
But PHP does allow you to use variable cases (as you have in your
example) if the value in the switch is a boolean (true or false). It can
be a little confusing if you're new to PHP (or programming in general)
but you'll get used to it after using it a few times.
Thanks,
Ash
http://www.ashleysheridan.co.uk
