How to determine if a checkbox is selected in a quick PHP sample

Hurry!! How do you determine if a checkbox is selected in PHP?
How does a checkbox in PHP determine if it is selected?

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The value obtained is not empty and is selected






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Check.html:

checkbox.php:
if ($_post)
{if ($_post[' select ']!= "") {echo "is not empty";} Else{echo "is Empty";}}
?>
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Can use JS to judge first, such as
if (form.checkname.checked) {}
If multiple, you can use the JS loop, the value of the check to make a string submission, or use the 4 floor method.
Submit to PHP page to judge once more.:-)
------Solution--------------------
PHP has no way of judging. Only when the form is submitted, the value is evaluated and then judged.
Can be done by the client JS to make judgments.
Detects if his checked is true

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