如何动态检查$ _POST变量为NULL

Question

How to loop through $_POST variables sent by a form to make sure none of them are empty or NULL. For example, if a form has 15 fields and is submitted. How to check that each of those 15 fields actually contained something other than NULL. I have multiple Forms but one validator class so I cannot specify the variable in the post array that need to be checked for each form.

I tried using foreach but that seemed to clear the $_POST array or corrupt it for some reason? The not working code is given below. If I var_dump($_POST) before I use the foreach and after the foreach I get an empty array after, but the correct values before. So I thing foreach is out of the question. Any Ideas?

foreach($_POST as $key => $value)
{
if ($value==NULL)
header ("Location: index.php")
}

Answer 1

You will not get any NULL values in $_POST array. If the form is submitted successfully and if the HTML form was not tampered with then all the fields will at least have some value or they will be empty ''. Do not use empty() function of PHP because it even considers 0 and a few other values as empty which might actually be the value. I believe this would be the correct way to write your code:

foreach ($_POST as $key => $value) {
    if ($value === '')
        header("Location: index.php");
}