You can use –
$isTouch = isset($variable);
It will return true
if the $variable
is defined. If the variable is not defined it will return false
.
Note: It returns TRUE if the variable exists and has a value other than NULL, FALSE otherwise.
If you want to check for false
, 0
, etc., you can then use empty()
–
$isTouch = empty($variable);
empty()
works for –
- “” (an empty string)
- 0 (0 as an integer)
- 0.0 (0 as a float)
- “0” (0 as a string)
- NULL
- FALSE
- array() (an empty array)
- $var; (a variable declared, but without a value)