Convert boolean to integer value php
Is there any builtin function for PHP that will take a boolean value and return its integer equivalent? 0 for FALSE, 1 for TRUE? Of course you can easily create a function to do so, I’m just asking if there is a builtin function inside of PHP. I already tried intval() and casting it to (int) but they didnt work, they return 0 in both cases of TRUE and FALSE.
Edit : the problem was that it wasnt really a boolean, it was a string «false», «true», php didnt detect the jquery post that it passed a boolean. problem solved, thanks !
Php Solutions
Solution 1 — Php
$myInt = (int)$myBoolean should work
Solution 2 — Php
Just add a «+» before your variable like this :
$myBool = true; var_dump(+$myBool); ouputs: int(1); Solution 3 — Php
// cast to Integer echo (int)true; // 1 echo (int)false; // 0 // get the integer value from argument echo intval(true); // 1 echo intval(false); // 0 // simply echoing true returns 1 echo true; // 1 // you can even add those values echo true + true; // 2 Solution 4 — Php
If you are unsure of the data type see the example below, it works on strings, integers and booleans.
$options = [ TRUE, FALSE, 'true', 'false', 1, 0, '1', '0', 'on', 'off', 'yes', 'no' ]; foreach ( $options as $option ) < $bool = filter_var( $option, FILTER_VALIDATE_BOOLEAN ); // TRUE or FALSE print (int) $bool . ' '; // 1 or 0 > // Outputs: 1 0 1 0 1 0 1 0 1 0 1 0 ?> filter_var( $var, FILTER_VALIDATE_BOOLEAN ) will return bool(true) or bool(false) then simply cast as integer.
filter_var — Filters a variable with a specified filter
Solution 5 — Php
If you are getting your value in from JSON I.E. Via an AJAX POST, the value will come in as a string (As you have found). A way around this is to compare the true/false string and then cast the bool to an int
$requestBool = $_REQUEST['bool_value']; //This is 'true' or 'false' $myInt = (int)($requestBool === 'true'); echo $myInt; //returns: 0 or 1 Solution 6 — Php
You can do multiple castings in a single go:
$isTest = 'true'; (int)(bool)$isTest echo $isTest; // this outputs 1 Solution 7 — Php
var_dump((bool) 1); // bool(true) var_dump((bool) 0); // bool(false) Php true to int
Much of the confusion about booleans (but not limited to booleans) is the fact that PHP itself automatically makes a type cast or conversion for you, which may NOT be what you want or expect. In most cases, it’s better to provide functions that give your program the exact behavior you want.
function boolNumber ( $bValue = false ) < // returns integer
return ( $bValue ? 1 : 0 );
>
function boolString ( $bValue = false ) < // returns string
return ( $bValue ? ‘true’ : ‘false’ );
>
$a = true ; // boolean value
echo ‘boolean $a AS string = ‘ . boolString ( $a ) . ‘
‘ ; // boolean as a string
echo ‘boolean $a AS number = ‘ . boolNumber ( $a ) . ‘
‘ ; // boolean as a number
echo ‘
‘ ;
$b = ( 45 > 90 ); // boolean value
echo ‘boolean $b AS string = ‘ . boolString ( $b ) . ‘
‘ ; // boolean as a string
echo ‘boolean $b AS number = ‘ . boolNumber ( $b ) . ‘
‘ ; // boolean as a number
echo ‘
‘ ;
$c = boolNumber ( 10 > 8 ) + boolNumber (!( 5 > 10 )); // adding booleans
echo ‘integer $c = ‘ . $c . ‘
‘ ;
?>
Results in the following being printed.
boolean $a AS string = true
boolean $a AS number = 1
boolean $b AS string = false
boolean $b AS number = 0
In other words, if we know what we want out of our program, we can create functions to accommodate. Here, we just wanted ‘manual control’ over numbers and strings, so that PHP doesn’t confuse us.
Php true to int
Cast a string to binary using PHP < 5.2.1
I found it tricky to check if a posted value was an integer.
is_int ( $_POST [ ‘a’ ] ); //false
is_int ( intval ( «anything» ) ); //always true
?>
A method I use for checking if a string represents an integer value.
$foo [ ‘ten’ ] = 10 ; // $foo[‘ten’] is an array holding an integer at key «ten»
$str = » $foo [ ‘ten’]» ; // throws T_ENCAPSED_AND_WHITESPACE error
$str = » $foo [ ten ] » ; // works because constants are skipped in quotes
$fst = (string) $foo [ ‘ten’ ]; // works with clear intention
?>
It seems (unset) is pretty useless. But for people who like to make their code really compact (and probably unreadable). You can use it to use an variable and unset it on the same line:
$hello = ‘Hello world’ ;
print $hello ;
unset( $hello );
$hello = ‘Hello world’ ;
$hello = (unset) print $hello ;
?>
Hoorah, we lost another line!
It would be useful to know the precedence (for lack of a better word) for type juggling. This entry currently explains that «if either operand is a float, then both operands are evaluated as floats, and the result will be a float» but could (and I think should) provide a hierarchy that indicates, for instance, «between an int and a boolean, int wins; between a float and an int, float wins; between a string and a float, string wins» and so on (and don’t count on my example accurately capturing the true hierarchy, as I haven’t actually done the tests to figure it out). Thanks!
May be expected, but not stated ..
Casting to the existing (same) type has no effect.
$t = ‘abc’; // string ‘abc’
$u=(array) $t; // array 0 => string ‘abc’ $v=(array) $u; // array 0 => string ‘abc’
Correct me if I’m wrong, but that is not a cast, it might be useful sometimes, but the IDE will not reflect what’s really happening:
class MyObject /**
* @param MyObject $object
* @return MyObject
*/
static public function cast ( MyObject $object ) return $object ;
>
/** Does nothing */
function f () <>
>
class X extends MyObject /** Throws exception */
function f () < throw new exception (); >
>
$x = MyObject :: cast (new X );
$x -> f (); // Your IDE tells ‘f() Does nothing’
?>
However, when you run the script, you will get an exception.
In my much of my coding I have found it necessary to type-cast between objects of different class types.
More specifically, I often want to take information from a database, convert it into the class it was before it was inserted, then have the ability to call its class functions as well.
The following code is much shorter than some of the previous examples and seems to suit my purposes. It also makes use of some regular expression matching rather than string position, replacing, etc. It takes an object ($obj) of any type and casts it to an new type ($class_type). Note that the new class type must exist:
Looks like type-casting user-defined objects is a real pain, and ya gotta be nuttin’ less than a brain jus ta cypher-it. But since PHP supports OOP, you can add the capabilities right now. Start with any simple class.
class Point protected $x , $y ;
public function __construct ( $xVal = 0 , $yVal = 0 ) $this -> x = $xVal ;
$this -> y = $yVal ;
>
public function getX () < return $this ->x ; >
public function getY () < return $this ->y ; >
>
$p = new Point ( 25 , 35 );
echo $p -> getX (); // 25
echo $p -> getY (); // 35
?>
Ok, now we need extra powers. PHP gives us several options:
A. We can tag on extra properties on-the-fly using everyday PHP syntax.
$p->z = 45; // here, $p is still an object of type [Point] but gains no capability, and it’s on a per-instance basis, blah.
B. We can try type-casting it to a different type to access more functions.
$p = (SuperDuperPoint) $p; // if this is even allowed, I doubt it. But even if PHP lets this slide, the small amount of data Point holds would probably not be enough for the extra functions to work anyway. And we still need the class def + all extra data. We should have just instantiated a [SuperDuperPoint] object to begin with. and just like above, this only works on a per-instance basis.
C. Do it the right way using OOP — and just extend the Point class already.
class Point3D extends Point protected $z ; // add extra properties.
public function __construct ( $xVal = 0 , $yVal = 0 , $zVal = 0 ) parent :: __construct ( $xVal , $yVal );
$this -> z = $zVal ;
>
public function getZ () < return $this ->z ; > // add extra functions.
>
$p3d = new Point3D ( 25 , 35 , 45 ); // more data, more functions, more everything.
echo $p3d -> getX (); // 25
echo $p3d -> getY (); // 35
echo $p3d -> getZ (); // 45
?>
Once the new class definition is written, you can make as many Point3D objects as you want. Each of them will have more data and functions already built-in. This is much better than trying to beef-up any «single lesser object» on-the-fly, and it’s way easier to do.
Re: the typecasting between classes post below. fantastic, but slightly flawed. Any class name longer than 9 characters becomes a problem. SO here’s a simple fix:
function typecast($old_object, $new_classname) if(class_exists($new_classname)) // Example serialized object segment
// O:5:»field»:9: $old_serialized_prefix = «O:».strlen(get_class($old_object));
$old_serialized_prefix .= «:\»».get_class($old_object).»\»:»;
$old_serialized_object = serialize($old_object);
$new_serialized_object = ‘O:’.strlen($new_classname).’:»‘.$new_classname . ‘»:’;
$new_serialized_object .= substr($old_serialized_object,strlen($old_serialized_prefix));
return unserialize($new_serialized_object);
>
else
return false;
>
Thanks for the previous code. Set me in the right direction to solving my typecasting problem. 😉
If you have a boolean, performing increments on it won’t do anything despite it being 1. This is a case where you have to use a cast.
I have 1 bar.
I now have 1 bar.
I finally have 2 bar.
Checking for strings to be integers?
How about if a string is a float?
/* checks if a string is an integer with possible whitespace before and/or after, and also isolates the integer */
$isInt = preg_match ( ‘/^\s*(8+)\s*$/’ , $myString , $myInt );
echo ‘Is Integer? ‘ , ( $isInt ) ? ‘Yes: ‘ . $myInt [ 1 ] : ‘No’ , «\n» ;
/* checks if a string is an integer with no whitespace before or after */
$isInt = preg_match ( ‘/^6+$/’ , $myString );
echo ‘Is Integer? ‘ , ( $isInt ) ? ‘Yes’ : ‘No’ , «\n» ;
/* When checking for floats, we assume the possibility of no decimals needed. If you MUST require decimals (forcing the user to type 7.0 for example) replace the sequence:
2+(\.3+)?
with
6+\.5+
*/
/* checks if a string is a float with possible whitespace before and/or after, and also isolates the number */
$isFloat = preg_match ( ‘/^\s*(5+(\.4+)?)\s*$/’ , $myString , $myNum );
echo ‘Is Number? ‘ , ( $isFloat ) ? ‘Yes: ‘ . $myNum [ 1 ] : ‘No’ , «\n» ;
/* checks if a string is a float with no whitespace before or after */
$isInt = preg_match ( ‘/^1+(\.5+)?$/’ , $myString );
echo ‘Is Number? ‘ , ( $isFloat ) ? ‘Yes’ : ‘No’ , «\n» ;