CODEWITHSUNDEEP
phpmysql
lethalMango
lethalMango

Reputation: 4491

Quick way to change empty $_POST data to NULL

I currently have a form with over 50+ fields, with roughly 20 optional fields.

Is there any easy way to process $_POST data in one hit to remove empty strings and change them to NULL prior to inserting into the database, or do they have to be done one by one in the following method:

if ($_POST['field_x'] == "") {
    $_POST['field_x'] = NULL;
}

Upvotes: 3

Views: 9682

Answers (7)

Edward
Edward

Reputation: 2359

You can do something like this:

foreach ($_POST as $k => $v) {
    if(empty($v) || $v === '') {
        $_POST[$k] = null;
    }
}

echo '<pre>';var_dump($_POST);echo '</pre>';

Upvotes: 0

MaggusK
MaggusK

Reputation: 645

based on the answer of hakre my solution for this is:

foreach ($_POST as &$v) {
  $v = (is_numeric($v) ? $v : ($v === "" ? "NULL" : "'" . $v . "'"));
}
unset($v);

So afterwards I concat my SQL command like this:

$sql = "INSERT INTO $mytable (number, name, description)
             VALUES (" . $_POST['number'] . ","
                       . $_POST['name'] . ","
                       . $_POST['description'] . ")";

In fact I got no other method working to really get NULL for all emtpy $_POST variables into the database field.

Upvotes: 0

fagad
fagad

Reputation: 1

Assign $_POST['data'] to a variable, like $a=$_POST['data']; after usage of variable $a, make it empty like $a=""; or $a=null;

Upvotes: -1

anonfornow
anonfornow

Reputation: 1

(isset($_POST['x']) ? $_POST['x'] : NULL)

Easier inline method for PDO binding. isset() is a special function. You can't call another function to then check isset() on a variable.

Example:

$conn = new PDO($pdo_connection, $pdo_username, $pdo_password);
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);    
$stmt = $conn->prepare('SELECT * FROM `t` WHERE `x`=:x');
$stmt->bindValue(':x', (isset($_POST['x']) ? $_POST['x'] : NULL), PDO::PARAM_STR);
$stmt->execute();

Upvotes: 0

hakre
hakre

Reputation: 197787

Setting all elements that are an empty string to NULL:

foreach ($_POST as &$v) {
    if ($v !== "") {
        continue
    }
    $v = NULL;
}
unset($v); // remove the reference (alias) to the last element of $_POST

Upvotes: 4

Luwe
Luwe

Reputation: 3034

You can use array_filter:

$post = array_filter($_POST);

http://php.net/manual/en/function.array-filter.php

If no callback is supplied, all entries of input equal to FALSE (see converting to boolean) will be removed.

To only remove empty strings you can use:

function drop_empty($var)
{
  return ($var === '') ? NULL : $var;
}

$post = array_filter($_POST, 'drop_empty');

If you don't want to drop values, but only want to set them to NULL: use array_map:

$post = array_map('drop_empty', $_POST);

Upvotes: 10

Paul
Paul

Reputation: 141827

This is nice and concise, but it will also remove POST values like the integer 0 or anything else that evaluates to false when cast to (bool)

$_POST = array_filter($_POST);

If that won't work for you you can use a callback function that compares using === to ""

You should also note that this is more like calling unset() rather than setting the array element to NULL, which is quite similar and probably good enough / even better for your situation.

Upvotes: 3

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