Re: How Do I make Global Scope Variables Available to Functions

> On May 28, 2018, at 5:58 PM, John <john.iliffe@iliffe.ca> wrote: > > On Sun, 2018-05-27 at 19:23 -0700, Jeffry Killen wrote: >> On May 27, 2018, at 5:46 PM, John wrote: >> >>> I am writing a PHP script that has a number of variables that (I >>> think) are in >>> Global scope; that is, they are defined inline before the first >>> command of the >>> script. Note that these are not necessarily constants as shown in >>> the example I >>> included; most of them can be changed by the script. >>> >>> I have functions defined following these variables and before the >>> commands in >>> the script appear, but when they are called, the functions report >>> the variables >>> as undefined. This means I have to pass all the Globals to each >>> function as a >>> call argument. >>> >>> A trivial script illustrating the problem is below. >>> >>> This seems odd but I don't see what I am doing wrong. Any >>> suggestions? >>> >>> PHP 5.6.30 called through php-fpm on Apache. >>> >>> Thanks in advance. >>> >>> John >>> ------------------------------------ >>> test.php - working version >>> >>> This variant passes a variable in global scope explicitly as a >>> parameter. It >>> displays correctly on the browser screen. >>> >>> >>> <?php >>> >>> $bad_line = "This line should display on screen."; >>> >>> // sample function that works >>> function sample1($bad_line) >>> { >>> return "\n" . $bad_line . "\n"; >>> } >>> >> >> This function could also be written >> function sample1($a) >> { >> return "\n" . $a . "\n"; >> } >>> echo sample1($bad_line); >> >> But it looks like you've answered your own question. >> If you wanted to have the function, or another function >> alter $bad_line, it would need to be passed by reference >> >> echo sample1(&$bad_line) .... as I understand it. >> >>> // this call does work >>> echo sample1($bad_line); >>> >>> exit; >>> ?> >>> >>> >>> >>> test.php - doesn't work >>> >>> This variant does not work; it throws error: >>> >>> [Sun May 27 20:17:46.779348 2018] [proxy_fcgi:error] [pid 893:tid >>> 139838497978112] [client 192.168.1.104:37732] AH01071: Got error >>> 'PHP message: >>> PHP Notice: Undefined variable: bad_line in /httpd/iliffe/yrarc/ >>> test.php on >>> line 8\n' >>> >>> <?php >>> >>> $bad_line = "This line should display on screen."; >>> >>> // sample function that doesn't work >>> function sample1() >>> { >>> return "\n" . $bad_line . "\n"; >>> } >>> >>> // this call doesn't work >>> echo sample1(); >>> >>> exit; >>> >>> ?> >>> >>> > Thanks Jeffry. Yes, I do have a workaround as you suggested but given the > number of variables being passed it is unworkable to have to pass them all as > arguments to the function. I have been passing them as an array as I noted in > an earlier reply but that is getting unwieldy and will be a maintenance > nightmare. > > The original variables, so far anyway, are not changed within any function but > can vary between calls to the various functions. Basically it is running in a > loop that sets up the various required variables and then passes everything to > one or another function for database processing and/or printing. > > Thanks for the suggestion though. I'm getting an education here! > > John > >> When I have multiple arguments to pass to a function I prefer using an associative array. So, $arraysamp = [‘fruit’=>’apples’, ‘clothing’=>’socks’]; function handleArray($a) { switch($a[‘fruit’]) { case ‘apples’: // process apples; return “apple pie”; break; default: return “input argument error”; break; } // other code for processing $a[‘clothing'] } echo handleArray($arraysamp); Also, You have declared the global variable in the global script file scope. As I understand it global is for use inside of a function that elevates the declared variable to the global scope. Your error may be due to declaring a variable that is already in the global scope by default, as global. I understand your concern because I also do a significant amount of javascript programming and in that language the scope of a function can see a variable in the global scope by default: var cat = ’siamese’; function getCat() { alert(cat) } getCat() // dialog in browser produces “siamese” My experience and knowledge of php informs me that this is not possible as such. I hope this can be helpful. Jeff K