Learning PHP, MySQL, JavaScript, and CSS, 2nd Edition

Chapter 11 Answers

1. The associative arrays used to pass submitted form data to PHP are $_GET for the GET method and $_POST for the POST method.

2. The register_globals setting was the default in versions of PHP prior to 4.2.0. It was not a good idea because it automatically assigned submitted form field data to PHP variables, thus opening up a security hole for potential hackers, who could attempt to break into PHP code by initializing variables to values of their choice.

3. The difference between a text box and a text area is that although they both accept text for form input, a text box is a single line, whereas a text area can be multiple lines and includes word wrapping.

4. To offer three mutually exclusive choices in a web form, you should use radio buttons, because checkboxes allow multiple selections.

5. You can submit a group of selections from a web form using a single field name by using an array name with square brackets, such as choices[], instead of a regular field name. Each value is then placed into the array, whose length will be the number of elements submitted.

6. To submit a form field without the user seeing it, place it in a hidden field using the parameter type="hidden".

7. You can encapsulate a form element and supporting text or graphics, making the entire unit selectable with a mouse-click, by using the <label> and </label> tags.

8. To convert HTML into a format that can be displayed but will not be interpreted as HTML by a browser, use the PHP htmlentities function.