Google Hacks 2Nd Edition [Electronic resources] نسخه متنی

Hack 18. Hack Your Own Google Search Form

Build your own personal, task-specific Google
search form .

If you
want to do a simple search with Google, you don't
need anything but the standard Simple Search form (the Google home
page). But if you want to craft specific Google searches that
you'll be using on a regular basis or providing for
others, you can simply put together your own personalized search
form.

Start with your garden-variety Google search form; something like
this will do nicely:

<!-- Search Google -->
<form method="get" action="http://www.google.com/search">
<input type="text" name="q" size=31 maxlength=255 value=">
<input type="submit" name="sa" value="Search Google">
</form>
<!-- Search Google -->

This is a very simple search form. It takes your query and sends it
directly to Google, adding nothing to it. But you can embed some
variables to alter your search as needed. You can do this in two
ways: via hidden variables or by adding more input to your form.

1.30.1. Hidden Variables

As long as you know how to identify a search option in Google, you
can add it to your search form via a hidden variable. The fact that
it's hidden just means that form users will not be
able to alter it. They won't even be able to see it
unless they take a look at the source code. Let's
take a look at a few examples.

While it's perfectly legal HTML to put your hidden variables anywhere between the opening and closing <form> tags, it's rather tidy and useful to keep them all together after all the visible form fields.

File Type
As the name suggests, file
type specifies filtering your results by a particular file type
(e.g., Word .doc, Adobe
.pdf, PowerPoint .ppt,
plain text .txt). Add a PowerPoint file type
filter, for example, to your search form, like so:

<input type="hidden" name="as_filetype" value="PPT">

Site Search
Narrows your search to
specific sites. While a suffix like .com will
work just fine, something more fine-grained like the
example.com domain is probably better suited:

<input type="hidden" name="as_sitesearch" value="example.com">

URL Component
Specifies a particular path component to look for in
URLs. This
can include a domain name but doesn't have to. The
following tries to tease out documentation in your result set:

<input type="hidden" name="hq" value="inurl:docs">

Date Range
Narrows your search to
pages indexed within the stated number of months. Acceptable values
are between 1 and 12. Restricting our results to items indexed only
within the last seven months is just a matter of adding:

<input type="hidden" name="as_qdr" value="m7">

Number of Results
Indicates the number of results that
you'd like appearing on each page, specified as a
value of num between 1 and 100; the following asks
for 50 per page:

<input type="hidden" name="num" value="50">

What would you use this for? If you're regularly
looking for an easy way to create a search engine that finds certain
file types in a certain place, this works really well. If this is a
one-time search, you can always just hack the results URL
["Understanding Google URLs"
earlier in this chapter], tacking the variables and their associated
values on to the URL of the results page.

1.30.2. Mixing Hidden File Types: An Example

The site tompeters.com (http://www.tompeters.com) contains several
PowerPoint (.ppt) files. If you want to find
just the PowerPoint files on their site, you'd have
to figure out how their site search engine works or pester them into
adding a file type search option. But you can put together your own
search form that finds PowerPoint presentations on the tompeters.com
site.

Even though you're creating a handy search form this way, you're still resting on the assumption that Google's indexed most or all of the site that you're searching. Until you know otherwise, assume that any search results Google gives you are incomplete.

Your form looks something like:

<!-- Search Google for tompeters.com PowerPoints -->
<form method="get" action="http://www.google.com/search">
<input type="text" name="q" size=31 maxlength=255 value=">
<input type="submit" name="sa" value="Search Google">
<input type="hidden" name="as_filetype" value="ppt">
<input type="hidden" name="as_sitesearch" value="tompeters.com">
<input type="hidden" name="num" value="100">
</form>
<!-- Search Google for tompeters.com PowerPoints -->

Using hidden variables is handy when you want to search for one
particular thing all the time. But if you want to be flexible in what
you're searching for, creating an alternate form is
the way to go.

1.30.3. Creating Your Own Google Form

Some variables best stay hidden; however, for other options, you can
let your form users be much more flexible.

Let's go back to the previous example. You want to
let your users search for PowerPoint files, but you also want them to
be able to search for Excel files and Microsoft Word files. In
addition, you want them to be able to search tompeters.com, the State
of California, or the Library of Congress. There are obviously
various ways to do this user-interface-wise; this example uses a
couple of simple pull-down menus:

<!-- Custom Google Search Form-->
<form method="get" action="http://www.google.com/search">
<input type="text" name="q" size=31 maxlength=255 value=">
<br />
Search for file type:
<select name="as_filetype">
<option value="ppt">PowerPoint</option>
<option value="xls">Excel</option>
<option value="doc">Word</option>
</select>
<br />
Search site:
<select name="as_sitesearch">
<option value="tompeters.com">TomPeters.com</option>
<option value="state.ca.us">State of California</option>
<option value="loc.gov">The Library of Congress</option>
</select>
<input type="hidden" name="num" value="100">
<input type="submit" value="Search Google">
</form>
<!-- Custom Google Search Form-->

FaganFinder (http://www.faganfinder.com/engines/google.shtml)
is a wonderful example of a thoroughly customized form.