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"Web task"
There are other names, like “Web query” or "Net query," but the
meaning is the same: to go to the Web and not simply download, but do something
especially useful - for example extract particular parts of data on
the web page, download selected files, and perform various other actions.
".vwt file"
Any web task has a lot of parameters to be saved somewhere. Our
software saves them in an XML file with the
extension “.vwt”. These files have a specific XML structure. It is not
recommended to access them directly because the structure can and will be
changed.
"Record - create navigation model "
As indicated above, a web extraction task can have a complicated
navigation path. In "Visual Web Task" there is a step when the user records
navigation to the final web page. This record can contain one or several web
sites, and will be a model for how the spider is to behave.
"ROWS" and "COLUMNS "
If you have searched for something using Yahoo or AltaVista, you
probably noticed that the results of your search usually have the same logical
structure. There is some Web address to go to and a short description of the
address. Let’s call one search result a ROW, and let’s divide the row into
columns . In our simple example it’ll be just 2 COLUMNS – Web address and
explanation. It’s very important to create a correct rows/columns layout for
the Web task. For any row and column intersection, additional actions can be
specified like extract email addresses from, download file, or extract
selected text.
‘Next Page’
Search results are usually represented as a list divided into pages.
You should define the “Next Page” action to tell Web Task how to load the next
page.
Steps of the wizard
General Buttons:
‘Help’ – displays help pages
‘Next’ - takes You to the next step of the wizard
‘Back’ - takes You one step back
‘Cancel’ – terminates the wizard
‘.vwt file’
On the first step of the wizard you have to create new or select
existing web task and library files. This step has following buttons:
”New” - creates a new web task file. You’ll be prompted to specify a
new file name.
”Browse” – opens the browse window to find an existing web task file on the
hard disk or other data storage device.
”New Task” – prompts for a new Task name and creates an empty task project.
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