PHP为空：仅将一个0作为字符串？

Question

I want to take a single0 as a string only for db injection but not 00 or 0000 as string.

$post["content"] = '00';

if (empty($post["content"]) && $post["content"] !== '0') 
{
     echo "this field must not be empty!";
}

It does not return it as an error.

What should I do?

Answer 1

Use !trim() instead:

<?php
$post["content"] = '00';


if ($post["content"] !== '0' && !trim($post["content"], '0')) 
{
    echo "this field must not be empty!";
}
?>