the best way to check if a url is valid?

[msapola]

i want to use php to detect the string which is called $myoutput & check it if it's a valid link syntax or just a normal text.the function should recognise all links formats including the ones contains GET parametersit is preferred to not call that link to see if it's a valid link syntax by doing CURL or file_get_contents.maybe with some preg match. or another solutionThanks