How to check variable types in PHP
To check variable types in PHP, we have many variable handling functions available. Below is the list of functions I am going to explain.
- Click to read about PHP variables.
- Click to read about data types.
- Click to read about how to check data types.
Function list to check variable types.
- is_array()
- is_bool()
- is_double()
- is_float()
- is_int()
- is_long()
- is_integer()
- is_numeric()
- is_object()
- is_resource()
- is_null()
- is_string()
is_array() function in PHP
PHP is_array() function checks whether the passed argument is an array type or not.
Returns true if argument is array, otherwise returns false.
1 2 3 4 5 6 7 8 9 10 11 12 13 |
$arr = [1, 2]; var_dump(is_array($arr)); /* result is bool(true) */ $arr = 'not array'; var_dump(is_array($arr)); /* result is bool(false) */ |
is_bool() function in PHP
PHP is_bool() function checks whether the passed argument is of Boolean type (true/false) or not.
Returns true if argument is Boolean type, otherwise returns false.
1 2 3 4 5 6 7 8 9 10 11 12 13 |
$var = 1; var_dump(is_bool($var)); /* result is bool(true) */ $var = true; var_dump(is_bool($var)); /* result is bool(false) */ |
is_double() function in PHP
PHP is_double() function checks whether the passed argument is of double/float/real type or not.
Returns true if argument is double/float/real type, otherwise returns false.
is_float() function in PHP
PHP is_float() function is alias of is_double() function.
is_real() function in PHP
PHP is_real() function is alias of is_double() function.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 |
$var = 1.3; var_dump(is_double($var)); var_dump(is_float($var)); var_dump(is_real($var)); /* result is bool(true) bool(true) bool(true) */ $var = 02; var_dump(is_double($var)); var_dump(is_float($var)); var_dump(is_real($var)); /* result is bool(false) bool(false) bool(false) */ |
is_int() function in PHP
PHP is_int() function checks whether the passed argument is is of type integer or not.
Returns true if argument is integer type, otherwise returns false.
is_long() function in PHP
PHP is_long() function is alias of is_int() function.
is_integer() function in PHP
PHP is_integer() function is alias of is_int() function.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 |
$var = 100; var_dump(is_int($var)); var_dump(is_long($var)); var_dump(is_integer($var)); /* result is bool(true) bool(true) bool(true) */ $var = 10.0; var_dump(is_int($var)); var_dump(is_long($var)); var_dump(is_integer($var)); /* result is bool(false) bool(false) bool(false) */ |
is_numeric() function in PHP
PHP is_numeric() function checks whether the passed argument is a numeric type value or not.
Returns true if argument is numeric type, otherwise returns false.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 |
$var = 100; var_dump(is_numeric($var)); /* result is bool(true) */ $var = '100'; var_dump(is_numeric($var)); /* result is bool(true) */ $var = 'hello'; var_dump(is_numeric($var)); /* result is bool(false) */ |
is_null() function in PHP
PHP is_null() function checks whether the passed argument is a null value or not.
Returns true if argument is null, otherwise returns false.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 |
$var = 100; var_dump(is_null($var)); /* result is bool(false) */ $var = ''; var_dump(is_null($var)); /* result is bool(false) */ $var = null; var_dump(is_null($var)); /* result is bool(true) */ |
is_object() function in PHP
PHP is_object() function checks whether the passed argument is an object i.e, instance of class or not.
Returns true if argument is instance of class, otherwise returns false.
1 2 3 4 5 6 7 8 9 10 11 |
class MyClass { } $obj = new MyClass(); var_dump(is_object($obj)); /* result is bool(true) */ |
is_resource() function in PHP
PHP is_resource() function checks whether the passed argument is a resource or not.
Returns true if argument is a resource, otherwise returns false.
1 2 3 |
$value = fopen(__DIR__.'/text.txt','r'); var_dump(is_resource($value)); fclose($value); |
is_string() function in PHP
PHP is_string() function checks whether the passed argument is a string or not.
Returns true if argument is a string, otherwise returns false.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 |
$var = "mystring"; var_dump(is_string($var)); /* result is bool(true) */ $var = "101"; var_dump(is_string($var)); /* result is bool(true) */ $var = 101; var_dump(is_string($var)); /* result is bool(false) */ |