Double-clicking on a thumbnail enters the full-screen image viewer mode. If the image’s Session has a Comment set, this comment is shown as a caption at the bottom of the screen.
While in full-screen mode, use the mouse or keyboard to control the view:
Exit full screen mode by middle-clicking or pressing the Escape key.
To advance to the next image, left-click, hit Spacebar, hit the Right arrow key, or hit Page Down. To go back to the previous image, right-click, hit Shift+Spacebar, hit the Left arrow key, or hit Page Up.
Press the Z key, Enter, or use the mouse wheel to toggle the Zoom level (Actual Size, or Stretch-to-Fit). If the image is shown Actual Size and is larger than the screen, you can use the mouse to pan around the image.
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To start an automatically-advancing slideshow, press any number key 1 to 9, representing the number of seconds to linger on each image. Press the 0 key to cancel the slideshow’s automatic advancement. By com-bining the slideshow with the Comment-displayed-as-Caption feature, you can use Fiddler as a basic photo presentation tool.
Various options are available to temporarily change the appearance of an image. Press H to flip the dis-played image horizontally, or V to flip the image vertically. Hit R to rotate the image by 90 degrees clock-wise. Press I to invert the image’s colors. Press S to apply a Sepia tone, and G to convert the image to grayscale. Pressing C will swap the green and blue colors in the image. Pressing E will convert the image to grayscale except for any Red pixels; this is a slow operation and may take several seconds for large images.
Press U to undo all of the manipulations made to the display of the image.
Press the Delete key to remove the image from the Gallery and advance to the next image.
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C O N T E N T B L O C K E R
The Content Blocker extension enables you to easily block selected content from download by returning a HTTP/404 response to the client. This functionality allows you to test your web applications’ behavior if content is blocked by an ad-blocker or the Tracking Protection feature found in IE8 and later.
To install the extension, you must download it from the Fiddler website and copy the DLL into your \Program Files\Fiddler2\Scripts folder. After installing the extension, a new ContentBlock menu will appear on the Fiddler main menu.
The ContentBlock menu offers several simple options:
Enabled When checked, blocking is enabled. When unchecked, no content will be blocked.
Block Paths When checked, requests are blocked if the URL path contains the text /ad
Edit Blocked Hosts When clicked, this menu item opens a new window that allows you to edit the list of hosts from which content will be blocked. The list consists of fully-qualified hostnames and is delimited by semicolons.
Always Block Flash When checked, Adobe Flash content will be blocked, regardless of its origin.
Block X-Domain Flash When checked, Adobe Flash content will be blocked if it originates from a different site than the requesting page. The Referer header is consulted in making this determination.
AutoTrim to 400 sessions When checked, this extension will automatically trim the Web Sessions list such that it contains no more than 400 sessions. The Keep Only dropdown on the Fiddler toolbar offers the same functionality.
Hide Blocked Sessions When checked, Sessions that are blocked will be hidden from the Web Sessions list.
You can easily add a host to the list of blocked hosts by right-clicking a Session in the Web Sessions list and choosing Block this Host from the context menu.
This extension was developed as an example of how to use the Fiddler extension model (its source is included in the download) and as such it offers some redundant functionality that can be found in other parts of Fiddler.
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T R A F F I C D I F F E R
The Traffic Differ extension aims to help you easily determine how two sets of captured traffic are different. This can be useful if, for instance, you have one SAZ file captured by a customer that encountered a problem from your site and another SAZ file captured which represents the “working” case.
The Traffic Differ enables you to load these two SAZ files and then compare the Sessions within them as a whole.
Alternatively, you can drag and drop Sessions from the current Web Sessions list to either of the Session lists and use those Sessions for comparison.
Two side-by-side Session lists show each Session’s status code, URL, response size, and a hash of the response body.
To compare any two individual Sessions between the two captures, select one Session in each list and then click the Compare Selected Session button. The file comparison tool will launch and compare the request and response headers and body text.
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F I D D L E R S C R I P T E D I T O R S
The Syntax Highlighting extensions package adds a new FiddlerScript tab to the main Fiddler UI and also provides a standalone Fiddler2 ScriptEditor application offering similar functionality. It also includes the SyntaxView Inspec-tors, described in the Inspectors chapter.