unset

问题 I have an id of a project and an id of a client that are sessions in php that are passed in JSON format. These are stored in global variables id_p and id_c so I can do multiple inserts and updates selects etc. with those ids. When the user selects another project or changes the page, I need to unset these variables. Can I pass a null value from php to the global vars to reset them? Is there a better way to do what I want? How could I store the php values on php only if the file is required?

问题 After learning how to "correctly" unset a node, I noticed that using PHP's unset() function leaves the tabs and spaces behind. So now I have this big chunk of white space in between nodes at times. I'm wondering if PHP iterates through blank spaces/returns/tabs and whether it would eventually slow down the system. I'm also asking whether there's an easy to remove the space unset leaves behind? Thanks, Ryan ADDED NOTE: This is how I removed the whitespaces after unsetting a node and it worked

问题 I got some cookie start by XYZ and I want to unset them when the user access to a specific route. So I code : foreach ($_COOKIE as $key => $value) if (preg_match('/^XYZ/', $key)) unset($_COOKIE[$key]); But the cookies still there. I really don't understand because when I do : foreach ($_COOKIE as $key => $value) if (preg_match('/^XYZ/', $key)) echo($_COOKIE[$key]); ... it works. So I wonder if it is possible to unset cookies like above. 回答1: reset a cookie like: setcookie($key,"",time()-3600)

问题 I've made a class that acts like an file wrapper. When user call delete method, i want to unset the object (actually $this). Is there a way (workaround) to do that? The manual said no, there is no way... 回答1: As far as I know, there is no way to destroy a class instance from within the class itself. You'll have to unset the instance within its scope. $myClass = new fooBar(); unset($myClass); Somewhat related: Doing the above will automatically call any existing __destruct() magic method of

问题 I have Created following class in flie index.class.php :- <?php class index{ public function loadTitle() { $title = "Welcome to My Website"; return $title; } } ?> and now, I am using it like below in my index.php file <?php require_once("index.class.php"); $obj = new index(); echo $obj->loadTitle(); ?> , now my question is Page will become heavy with lots of article and images, and i will expect 1500-2500 user every day in it. Do, i need to also unset memory, i know PHP has its own garbage

问题 Here my function that execute cmd as a Rebol instructions : exec-cmd: func [ cmd [ block! ] "Rebol instructions" /local err ] [ if error? err: try [ do cmd ] [ print mold disarm err ] ] When I launch the function, I've encountered the following error message : ** Script Error: err needs a value ** Where: exec-cmd ** Near: if error? err: try [ do cmd ] How can I avoid this message and manage the error ? 回答1: When the Rebol default evaluator sees a sequence of a SET-WORD! followed by a

问题 The problem sounds like this: The log-in using sessions works perfect on my localhost, but when the EXACTLY same files are uploaded to my host (hostgator), the sessions don't or, or they get messed up. Also the log-out feature doesn't work on the host. I've checked and every page has the session_start(); inside it. The session is not destroyed, even if my logout.php looks like this: <?php session_start(); $_SESSION = array(); session_unset(); session_destroy(); header("location:index.php");

问题 How can i unset a range of keys between say 70 to 80 in an array like this? [63] => Computer Science and Informatics [64] => Dentistry [65] => Development Studies [66] => Drama, Dance and Performing Arts [67] => Earth Systems and Environmental Sciences [68] => Economics and Econometrics [69] => Education [70] => Electrical and Electronic Engineering [71] => English Language and Literature [72] => Epidemiology and Public Health [73] => European Studies [74] => French [75] => General

问题 Trying to unset automatically all variables in script. Have tried this way: echo '<br /> Variables in Script before unset(): <br />'; print_r(array_keys(get_defined_vars())); echo '<br /><br />'; var_dump(get_defined_vars()); // Creates string of comma-separated variables(*) for unset. $all_vars = implode(', $', array_keys(get_defined_vars())); echo '<br /><br />'; echo '<br />List Variables in Script: <br />'; echo $all_vars; unset($all_vars); echo '<br /><br />'; echo '<br />Variables in

问题 I have this array $output which looks like this: Array( [0] => Array( [0] => 1a [1] => 1b [2] => 1c ) [1] => Array( [0] => 2a [1] => 2b [2] => 2c ) [2] => Array( [0] => 3a [1] => 3b [2] => 3c ) [3] => Array( [0] => 4a [1] => 4b [2] => 4c ) ) and so on... When I want to remove the second element I just use $output = unset($output[1]); to get the following: Array( [0] => Array( [0] => 1a [1] => 1b [2] => 1c ) [1] => Array( [0] => 3a [1] => 3b [2] => 3c ) [2] => Array( [0] => 4a [1] => 4b [2] =>