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

Chapter 16 Answers

1. You can send a form for validation prior to submitting it by adding the JavaScript onSubmit method to the <form> tag. Make sure that your function returns true if the form is to be submitted and false otherwise.

2. To match a string against a regular expression in JavaScript, use the test method.

3. Regular expressions to match characters not in a word could be any of /[^\w]/, /[\W]/, /[^a-zA-Z0-9_]/, and so on.

4. A regular expression to match either of the words “fox” or “fix” could be /f[oi]x/.

5. A regular expression to match any single word followed by any nonword character could be /\w+\W/g.

6. A JavaScript function using regular expressions to test whether the word “fox” exists in the string “The quick brown fox” could be:

   document.write(/fox/.test("The quick brown fox"))

7. A PHP function using a regular expression to replace all occurrences of the word “the” in “The cow jumps over the moon” with the word “my” could be:

   $s=preg_replace("/the/i", "my", "The cow jumps over the moon");

8. The HTML keyword used to precomplete form fields with a value is the value keyword, which is placed within an <input> tag and takes the form value="value".