Explain this function syntax

function StringCount($searchstring, $findstring)
        {
            return (strpos($searchstring, $findstring) === false ? 0 :  count(split($findstring, $searchstring)) - 1);
        }

it returns number of ocourances of substring in string, but why not just use count?

What means === false ? 0 : i mean how this called its not if or case is there way to call th开发者_如何学运维is type of writing?

http://www.php.net/manual/en/language.operators.comparison.php - about === http://www.php.net/manual/en/language.operators.comparison.php#language.operators.comparison.ternary - about (expr1) ? (expr2) : (expr3)

But, i think it is better to use substr_count() ( http://www.php.net/manual/en/function.substr-count.php ) in this function

This is a type of ternary operator (meaning it takes 3 operands), and is a short form of the if then else clause.

a ? b : c can be expanded as:

if(a)
{
   b
}
else
{
   c
}

So in essence it is something like this:

$strPos;
if (($searchstring, $findstring) === false) 
{
   $strPos=0 
}
else
{
   $strPos=count(split($findstring, $searchstring))
}

return strpos($strPos-1);

Because strpos returns Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE, such as 0 or "".

A good example is that StringCount("stackoverflow","stack") will return 0 if

function StringCount($searchstring, $findstring)
{
  return (strpos($searchstring, $findstring) == false ? 0 : count(split($findstring, $searchstring)) - 1);
}

It's a ternary condition

If strpos($searchstring, $findstring) is false, then 0, else count(split($findstring, $searchstring)) - 1

So if $findstring is NOT found in $searchstring, return 0

The reason you need 3 = for that false statement is strpos returns an integer of where the needle was found in the haystack. Buy using === you get the boolean.