filter_has_var()
(PHP 5 >= 5.2.0, PHP 7)
检测是否存在指定类型的变量
说明
filter_has_var(int $type,string $variable_name): bool
参数
- $type
INPUT_GET
、INPUT_POST
、INPUT_COOKIE
、INPUT_SERVER
、INPUT_ENV
里的其中一个。- $variable_name
要检查的变量名。
返回值
成功时返回TRUE
,或者在失败时返回FALSE
。
Through this example i think you can better understand if ( !filter_has_var(INPUT_GET, 'email') ) { echo "Email Not Found"; }else{ echo "Email Found"; } Output localhost/nanhe/test.php?email=1 //Email Found localhost/nanhe/test.php?email //Email Found http://localhost/nanhe/test.php //Email Not Found Consider on second example http://localhost/nanhe/test.php $_GET['email']="info@nanhe.in"; if ( !filter_has_var(INPUT_GET, 'email') ) { echo "Email Not Found"; }else{ echo "Email Found"; } But output will be Email Not Found
Please note that the function does not check the live array, it actually checks the content received by php: <?php $_GET['test'] = 1; echo filter_has_var(INPUT_GET, 'test') ? 'Yes' : 'No'; ?> would say "No", unless the parameter was actually in the querystring. Also, if the input var is empty, it will say Yes.
For people who are wondering whether "magic_quotes_gpc" has any affect on "filter_input" operation, here is an extract from a PHP source file: * As the input filter acts on input data before the magic quotes function mangles data, all access through the filter() function will not have any quotes or slashes added - it will be the pure data as send by the browser. So when using this function, there is no need to strip the slashes when "magic_quotes_gpc" is enabled.