<?php
class test{}
$a1 = null;
$a2 = "";
//$a3 =
$a4 = 0;
$a5 = '0';
$a6 = false;
$a7 = array();
//var $a8;
$a9 = new test();
for ($i=1; $i <=9 ; $i++) {
$s = 'a'.$i;
echo $i . ":";
var_dump(isset($$s));
echo '<br />';
}
echo '<br />';
for ($i=1; $i <=9 ; $i++) {
$s = 'a'.$i;
echo $i . ":";
var_dump(empty($$s));
echo '<br />';
}
That’s basically it
The above introduces the PHP judgment results of empty and isset parameters, including the content. I hope it will be helpful to friends who are interested in PHP tutorials.
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