isset（）或array_key_exists（）不能与$ _POST一起使用

Question

I have a VERY simple code, I dont know what I am doing wrong. I am sending post variables with Ajax, there are 3 checkboxes (an array) name="options[]".. I am receiving the right array, if I check Option1, Option2 or Option3, I get the correct Array.. but when I try to check and confirm them with isset() or with array_key_exist() it does not give me the right answers.. For example, if I only check Option 1 and 3, I get the following in the POST

   [options] => Array
    (
        [0] => option_one
        [1] => option_two
    )

I need to do some action only IF the certain key does NOT exist in the array.. I tried something like below..

  if (array_key_exists("option_one", $_POST['options'])) { 
     echo "Option one exists";
  } else {
     echo "option one does not exist";
  }

it returns flase results, then I tried using ! (not) before it, that returns the same result. Then I tried with isset($_POST['options']['option_one']) without any luck.. then I tried the following function to check again within the array..

function is_set( $varname, $parent=null ) {
  if ( !is_array( $parent ) && !is_object($parent) ) {
    $parent = $GLOBALS;
  }
  return array_key_exists( $varname, $parent );
} 

and used it like this

if (is_set("option_one", $_POST['options'])) {
  echo "Option one exists";
} else {
   echo "option one does not exist";
}

nothing works, it simply returns false value. I tried with $_REQUEST instead if $_POST but no luck, I have read many threads that isset() or array_key_exists() returns false values.. What is the solution for this ? any help would be highly appreciated.. I am tired of it now..

regards

Answer 1

option_one is not a key in the array, it's a value . The key is 0 . If anything, use:

in_array('option_one', $_POST['options'])

Answer 2

array_key_exists looks for the keys of the arrays. You are looking for the value. :)

What you want is

/**
 * Check wheter parameter exists in $_POST['options'] and is not empty
 *
 * @param $needle
 * @return boolean
 */
function in_options($needle)
{
    if (empty($_POST['options']))
        return false;

    return in_array($needle, $_POST['options']);
}

Answer 3

Are you sure you are getting the correct information in your options[] array? If you clicked option 1 and option 3, shouldn't the array look something like this?

   [options] => Array
    (
        [0] => option_one
        [1] => option_three
    )

---

Since isset() is a language construct and not a function , you may be able to rework the validation to be more efficient.

function in_options($needle)
{
    //Checking that it is set and not NULL is enough here.
    if (! isset($_POST['options'][0])) 
        return false;

    return in_array($needle, $_POST['options']);
}

The function empty() works , but I think that $_POST['options'][0] only needs to be checked for isset() at this point .