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Working with User Scripts

User scripts are a whole new way of working with JavaScriptrather than uploading them for use on your website, you install them in the browser for your own personal use. The following sections show you how to find useful scripts, and install and manage them.

Finding Scripts

Anyone can write user scripts, and many people have. Greasemonkey sponsors a directory of user scripts at http://userscripts.org/. There you can browse or search for scripts, or submit scripts you've written.

The script archive has thousands of scripts available. Along with general-purpose scripts, many of the scripts are designed to add features toor remove annoying features fromparticular sites.

Installing a Script

After you've found a script you wish to install, you can install it from the Web:

• In Firefox with Greasemonkey, open the script in the browser and then select Tools, Install This User Script from the menu.

• In IE with Turnabout, right-click on a link to the script and select Turnabout, Install Script.

You can also install a script from a local file. You'll use this technique to install your own script later this hour.

Managing Scripts

After you've installed one or more scripts with Greasemonkey, you can manage them by selecting Tools, Manage User Scripts from the Firefox menu. The Manage User Scripts dialog is shown in Figure 18.2.

Figure 18.2. Managing user scripts in Greasemonkey.

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The user scripts you have available are listed in the left column. Click on a script name to manage it:

• Use the Included Pages and Excluded Pages lists to control which pages the script works on. You can specify wildcards, such as * for all pages or *.google.com/* for all Google pages.

• Use the Enabled check box to enable or disable each script.

• Click the Uninstall button to remove a script.

• Click Edit to open a script in a text editor. When it is saved, it will immediately take effect on pages you load.

Turnabout for IE has a similar dialog. To access it, click the Reify button in the Turnabout toolbar and select Options. The dialog is similar to Greasemonkey's dialog, except that each script has a separate check box to enable or disable it. There is also an Install Feature button that prompts you for a new script to install. The Turnabout Options dialog is shown in Figure 18.3.

Figure 18.3. The Turnabout Options dialog.

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Testing User Scripts

If you have a script enabled, it will be activated as soon as you load a page that matches one of the Included Pages specified for the script. (The script is run after the page is loaded, but before the onLoad event.) If you want to make sure Greasemonkey is running, either try one of the scripts available for download, or type in the simple script in the next section.

Activating and Deactivating Greasemonkey or Turnabout

Sometimes you'll want to turn off Greasemonkey altogether, especially if one of the scripts you've installed is causing an error. To do this, right-click on the monkey icon in the lower-right corner of the browser window and select the Enabled option to deselect it. The monkey icon changes to a gray sad-faced monkey, and no user scripts will be run at all. You can re-enable it at any time using the same option.

With Turnabout for Internet Explorer, the procedure is similar: Click the Reify button in the Turnabout toolbar, and select the Enable Turnabout option. The icon changes to indicate that Turnabout is disabled. Choose Enable Turnabout again to re-enable it.