substr - php problem: strpos function not working

Question

why is the following php code not working:

$string = "123";
$search = "123";

if(strpos($string,$search))
{
    echo "found";
}else{
    echo "not found";
}

as $search is in $string - shouldn't it be triggered as found?

Answer 1

This is mentioned in the Manual: strpos()

This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE, such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

In your case the string is found at the index 0 and in php 0 == false

The solution is to just use the strict comparator

echo strpos($string,$search) === false
     ? "not found"
     : "found";

Another one

echo is_int(strpos($string,$search))
     ? "found"
     : "not found";

Or something ... lets say interesting :D Just for illustration. I don't recommend this one.

echo strpos('_' . $string,$search) // we just shift the string 1 to the right
     ? "found"
     : "not found";