PHP: Shortest way to check if a variable contains positive integer?

Question

I want to check if user input a positive integer number.

1    = true
+10  = true
.1   = false
-1   = false
10.5 = false


Just a positive number. 
No characters.
No special character.
No dot.
No minus sign.

I tried is_int() function but it is returning false even on positive integers. Is there a string to int problem?

Thanks

Answer 1

Something like this should work. Cast the value to an integer and compare it with its original form (As we use == rather than === PHP ignores the type when checking equality). Then as we know it is an integer we test that it is > 0. (Depending on your definition of positive you may want >= 0)

$num = "20";

if ( (int)$num == $num && (int)$num > 0 )

Answer 2

the easiest way is:

if intval($x) > 0 echo "true"