Hi Chris, I've always used strstr() for this _exact_ same purpose and it's worked just fine. I find it much more useful as an InStr()-like function than for actually doing anything with the string it returns. You'll want to note that the parameter order is $haystack before $needle. That goes for strpos() as well. I noticed that in your original post, you're using a hypothetical function FoundInString($needle,$haystack). If you used the same order ($needle,$haystack) when you tried strstr() or strpos(), then it would fail because it's a bit difficult to find a haystack in a needle. =/
I _strongly_ recommend using one of these built-in functions, as they will run much faster than any programmer-defined function. Below I will explain how and potential pitfalls. Only problem I noticed is that you want the function to return an explicit true if the string is found (and false if it is not). Both functions will return an explicit false if the needle is not found, but neither return an explicit true. Don't let that stop you from using them though. If needle is found, strstr() returns a string and strpos() returns an integer (possibly 0). An if statement will consider a string (as returned by strstr()) as logically true, so you can use strstr() by itself inside an if statement. strpos() however returns the offset from the beginning of $haystack where it found $needle. This means that if $needle is at the beginning of $haystack, then it will return an integer 0. This of course is considered false by an if statement. However, you can use if(strpos($haystack,$needle)!==false). If you take a look at http://us3.php.net/manual/en/language.operators.comparison.php, you'll see that PHP's $a===$b and $a!==$b operators result in a true only if $a and $b are of the same type (bool, int, etc). Since an integer 0 is not the same as a boolean false, strpos()!==false will not choke when it returns an integer 0. If you want the function to return an explicit true because you want to assign the result to a variable, you can do this: $foo = (strstr($haystack,$needle)!==false) or anywhere else you plan to use it for that matter. Documentation for strstr() and strpos() http://us3.php.net/strstr http://us3.php.net/strpos -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
