National Instruments 322179A-01, LabView Animated Front Panel Image (.monitor URL)

Chapter 2 New Features in LabVIEW 5.1
LabVIEW 5.1 Addendum 2-60
© National Instruments Corporation
The following are some examples on how you would use this syntax:
• T o return the front panel image of the VI My VI.vi from the computer
foo using the default image type, depth, and quality, use the
following code:
http://foo/.snap?My%20VI.vi
• To return the front panel image of the VI Test 1.vi from the
computer foo using image depth=24 and image type=PNG, use the
following code:
http://foo/.snap?Test%201.vi&depth=24&type=png
• To embed the image of the VI Example.vi, in an HTML document
on the same system, use the following code:
<IMG SRC="/.snap?Example.vi">
• To embed the image of the VI Example.vi running on the computer
foo in any HTML document, use the following code:
<IMG SRC="http://foo/.snap?Example.vi">
Animated Front Panel Image (.monitor URL)
The .monitor URL signals the server to return an animated image of the
front panel of a VI currently in memory. The query parameters in the URL
specify the VI name, attributes of the animation, and attributes of the
image.
For example, you can write the URL for the animated image of the VI
Test Example.vi, which updates once every two seconds for three
minutes, as follows:
http://web.server.addr/.monitor?Test+Example.vi&refresh=2&lifespan=180
For Netscape Navigator browsers, the server uses the server-push method
of animation. The server accomplishes this animation by taking subsequent
snapshots of the front panel image and sending them to the client. With
other browsers, the server uses the client-pull method of animation.
You must open the front panel of the VI to take snapshots for animated
images because closed front panels do not update the images of controls
when the value changes.