PHP boolean TRUE / FALSE?
I can't figure this out.
If I type:
function myfunction(){
......
if ...
return TRUE;
if ...
return FALSE;
}
Why can't I use it like this:
$result开发者_JAVA百科 = myfunction();
if ($result == TRUE)
...
if ($result == FALSE)
...
Or do I have to use:
$result = myfunction();
if ($result == 1)
...
if ($result == 0)
...
Or this:
$result = myfunction();
if ($result)
...
if (!$result)
...
I don't fully understand your question, but you can use any of the examples you provided, with the following caveats:
If you say if (a == TRUE)
(or, since the comparison to true
is redundant, simply if (a)
), you must understand that PHP will evaluate several things as true: 1, 2, 987, "hello", etc.; They are all "truey" values. This is rarely an issue, but you should understand it.
However, if the function can return more than true
or false
, you may be interested in using ===
. ===
does compare the type of the variables: "a" == true
is true
, but "a" === true
is false.
If you dont need to use the result variable $result furthermore, I would do the following shortest version:
if (myfunction()) {
// something when true
} else {
// something else when false
}
You could do like this
$result = myfunction();
if ($result === TRUE)
...
if ($result === FALSE)
...
You can use if($result == TRUE)
but that's an overkill as if($result)
is enough.
if($variable)
//something when truw
else
//something else when false
Remember that the value -1 is considered TRUE, like any other non-zero (whether negative or positive) number. FALSE would be 0 obv...
Double check you have gettype($result) == bool and NOT string.
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