$_POST for form submissions in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the value of the input named 'username' from the form submission.

PHP

<?php
$username = $_POST[[1]];
?>

Drag options to blanks, or click blank then click option'

A"user"

Busername

C"username"

D'user'

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around the input name.

Using the variable name without quotes.

Using the wrong input name.

In PHP, to get a value from a form submitted via POST, you use $_POST with the input's name as a string key. So, $_POST["username"] gets the value of the input named 'username'.

2fill in blank

medium

Complete the code to check if the form was submitted by checking if the 'submit' button was pressed.

PHP

<?php
if (isset($_POST[[1]])) {
    echo "Form submitted!";
}
?>

Drag options to blanks, or click blank then click option'

A"submit"

B"button"

C'submit_button'

D"send"

Attempts:

3 left

💡 Hint

Common Mistakes

Checking for the wrong key in $_POST.

Not using isset() to check existence.

Using single quotes inconsistently.

To check if the form was submitted, we check if the submit button's name exists in $_POST. Usually, the submit button is named 'submit', so we use isset($_POST["submit"]).

3fill in blank

hard

Fix the error in the code to safely get the 'email' input value and avoid undefined index errors.

PHP

<?php
$email = $_POST[[1]] ?? '';
?>

Drag options to blanks, or click blank then click option'

Auser_email

B'mail'

Cemail

D"email"

Attempts:

3 left

💡 Hint

Common Mistakes

Using the input name without quotes.

Using the wrong input name.

Not using the null coalescing operator.

To avoid undefined index errors, use the null coalescing operator (??) with the correct string key. The input name is 'email', so use $_POST["email"] ?? ''.

4fill in blank

hard

Fill both blanks to create an associative array with input names as keys and their values from the form submission.

PHP

<?php
$data = [
    'name' => $_POST[[1]],
    'age' => $_POST[[2]]
];
?>

Drag options to blanks, or click blank then click option'

A"name"

B"age"

C'age'

D'username'

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing single and double quotes inconsistently.

Using wrong input names.

Forgetting quotes around keys.

To get values from $_POST, use the input names as string keys. Here, 'name' and 'age' are keys, so use $_POST["name"] and $_POST['age'].

5fill in blank

hard

Fill all three blanks to loop through $_POST and print each key and value.

PHP

<?php
foreach ($_POST as [1] => [2]) {
    echo [3] . ': ' . [2] . "<br>";
}
?>

Drag options to blanks, or click blank then click option'

A$key

B$value

D$item

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same variable for key and value.

Using undefined variables.

Forgetting the arrow => in foreach.

In a foreach loop over $_POST, use $key for keys and $value for values. To print the key, use $key.