Two questions: Replacing whole words only + Reset button for a form

[White_Coffee]

I want to give users the possibilily to search and replace words in an article, just for fun 😉. Here is the code i'm using:

echo "<form action=\"" . $_SERVER['PHP_SELF'] . "\" method=\"post\">
<input type=\"text\" name=\"find_what\" value=\"";

if (isset($_POST['find_what'])) {
    echo $_POST['find_what'];
} else {
    echo "find what?";
}

echo "\" size=\"20\" maxlength=\"25\"/>
<input type=\"text\" name=\"replace_with\" value=\"";

if (isset($_POST['replace_with'])) {
    echo $_POST['replace_with'];
} else {
    echo "replace with what?";
}

echo "\" size=\"20\" maxlength=\"25\"/>
<input class=\"button\" name=\"submit\" value=\"Replace it!\" type=\"submit\" />
</form>\n";

And to process the form, i have this:

if (isset($_POST['find_what']) && isset($_POST['replace_with'])) {
    $_POST['find_what'] = preg_replace("/[_\W]/i", "", $_POST['find_what']);
    $_POST['replace_with'] = preg_replace("/[_\W]/i", "", $_POST['replace_with']);
    $article = str_replace($_POST['find_what'], $_POST['replace_with'], $article);
}

echo $article;

Everything works like a charm but there are issues i'd like to improve. My questions are:

1) How to search/replace whole words only?
2) How to make the search case insensitive?
3) How to add the Reset button to the form, if possible? This line:
<input type=\"reset\" name=\"reset\" value=\"Reset\" />
doesn't seem to do anything. 🙁 Tried a JavaScript solution i googled but it doesn't work for me either.

Since i'm a newbie, i feel totally lost and would be grateful for any help.

[Drakla]

For whole words use /b either side to search for word boundaries. Look at this for a great tutorial:
http://www.regular-expressions.info/wordboundaries.html

Case insensitivity is done with the i modifier, which you already seem to be using, and there's plenty more about that in the tutorial.

Reset button looks fine.

EDIT: just noticed you're using str_replace for the main part, and preg_replace for what seems like trimming of input.

Anyway, you'll be using preg_replace for the more complex replacements, too. Php5 also has str_ireplace for case insensitive replacement, but use preg if you don't have that.

[White_Coffee]

Many thanks for the tut link, just what i needed. 🙂

Now the code works perfectly albeit there may be an easier way of achieving this. But as i said, i'm a PHP newbie. Besides, regular expressions are definitely not my line 😃

if (isset($_POST['find_what']) && isset($_POST['replace_with'])) {
    $_POST['find_what'] = preg_replace("/\W/", "", $_POST['find_what']);
    $_POST['replace_with'] = preg_replace("/\W/", "", $_POST['replace_with']);
    $article = preg_replace("/\b" . $_POST['find_what'] . "\b/i", $_POST['replace_with'], $article);
}

echo $article;

However the Reset button problem remains. When i click it, nothing happens. Any ideas?

[LoganK]

<input type="reset" name="reset" value="Reset">

Will reset all the fields on the form.

[White_Coffee]

As i wrote in my first post, somehow it doesn't work for me. Otherwise i wouldn't have asked this question.

[LoganK]

That's the only reset button as defined by the W3C - there's no way it doesn't work. Are you sure you've coded it right? Make sure the button is within the <form></form> tags. Or post your form's HTML so I can see it.

[White_Coffee]

This is the rendered code:

<form action="/index.php" method="post">
<input type="text" name="find_what" value="word to search" size="20" maxlength="25" />
<input type="text" name="replace_with" value="word to replace with" size="20" maxlength="25" />
<input class="button" name="submit" value="Do it!" type="submit" />
<input class="button" name="reset" value="Reset" type="reset" />
</form>

I don't see what can be wrong here. 🙁

[LoganK]

It might be the "class" atribute but I highly doubt it...two things - just for the heck of it, try removing the class attribute, or try putting "type" as the first attribute.

If neither work, and that's how big the form will always be, then you can code a relatively simple JS function to clear it.

[White_Coffee]

Tried what you suggested -- no luck whatsoever. But thank you anyway.

Actually, upon pondering it on and off, i realized the Reset button wouldn't be of any help to me. Basically, that's what i need: say, a user replaced 'white' with 'black' through an article.
Now he/she should be able to reset the article to normal view with a single button click. But i'm not sure if it's possible...