(PHP 5 >= 5.2.0, PHP 7, PHP 8)
filter_has_var — 检测是否存在指定类型的变量
$type
, string $variable_name
) : bool
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。
成功时返回 true， 或者在失败时返回 false。
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.
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']="[email protected]";
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.