So why do we have empty() and isset() methods? We can not easily avoid them when working with non-existing array keys. They do not throw an Exception when accessing an undefined array key, so we can safely check for key or value presence in the array....
echo is_null($test),is_null(100),is_null($b=100); 运行结果:没有任何错误。 比较结果出来了:empty,isset输入参数必须是一个变量(php变量是以$字符开头的),而is_null输入参数只要是能够有返回值就可以。(常量,变量,表达式等)。在php手册里面,对于他们解析是:empty,isset 是一个语言结构而非函数,因此它...
empty, ";} else {echo " False "; } $my_var=0.0; if(empty($my_var)){echo " True Variable is empty, ";} else {echo " False "; } $my_var=Null; if(empty($my_var)){echo " True Variable is empty, ";} else {echo " False "; } $my_var=False; if(empty($my_var)){ech...
Search the page for theerror_logvalue. The file path listed here is the absolute file path of the PHP error log — visit that address on your server and you should see the PHP error log. If the value is empty, you’ll need to set a value to log errors on your site. ...
//check_admin()用于检查当前用户权限,如果是admin设置$is_admin变量为true,然后下面判断此变量是否为true,然后执行管理的一些操作。 //ex1.php if(check_admin()) { $is_admin=true; } if($is_admin) { do_something(); } ?> 这一段代码没有将$is_admin事先初始化为Flase,如果register_globals为On,...
$filter : filter_id($filter));if (false === $data) {return isset($default) ? $default : null;}}}if (!empty($type)) {switch (strtolower($type)) {case 'a': // 数组$data = (array) $data;break;case 'd': // 数字$data = (int) $data;break;case 'f': // 浮点$data = ...
1if ($request->hasAny(['name', 'email'])) { 2 // 3}If you would like to determine if a value is present on the request and is not empty, you may use the filled method:1if ($request->filled('name')) { 2 // 3}The whenFilled method will execute the given closure if a ...
$socket->on('checkScanCode',function ($key)use($io){ $redis = new MyRedis(); $userInfo = $redis::get($key); if(empty($userInfo)){ echo PHP_EOL.'Web端询问用户是否扫码:'.$key; $io->emit("waitScanCode"); }else{ $io->emit("SuccessScanCode", $userInfo); ...
if($request->isSuccessful()) {$results=$request->getResult();// Result data (usually array of objects, empty array means no results)}else{echo$request->getReason();// Failure reasonecho$request->getMessage();// Failure descriptive message (when available)echo$request->getRawResult();// ...
Check if has admins: hasAdmins Check if has report peers: hasReportPeers Check if is array or similar (traversable && countable && arrayAccess): isArrayOrAlike Check if peer is present in internal peer database: peerIsset Check if the 2FA recovery code sent using auth.requestPasswordRecovery...