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First an explanation of tags (also referred to as elements).
For those familiar with HTML you may already know that elements are the necessary
components to build even a simple HTML page. One example of an element is the
<B> tag. By using this element, textual data can be displayed in a
bold typeface. As an example the following text is wrapped in a bold tag:
HELLO. The code that produced this is as follows: <B>HELLO</B>
Elements are referred to as either inline, or block. The bold tag described above is
an inline type of element. Block elements are elements that generated a new block of
text. An example of a block element is the <P> tag. This tag produces a
new paragraph like the one you are reading right now. On the other hand, inline tags
do not create a new "paragraph" but instead change text formatting within a line (or inline)
as was seen with the previous bold example.
In the case of SteelArrow, the tags are neither inline nor block. In fact, they do not change
the display of the page, but instead are used to populate the page with data or used to control
the output with conditional statements, and looping constructs.
An example of a SteelArrow element is the <SAOUTPUT> element. This element allows
a developer to output data values at any place within a script. If a developer wishes to output
a data value, they will need to do so in an appropriate location. For example,
the output of the PARAM table, can be achieved with <SAOUTPUT VALUE=PARAM[]>, to do this
before the HTML tag <HTML> would break the rules of HTML, and the output may not be
seen. In this case the developer would be best to output the value within the HTML <BODY>
tag.
With SteelArrow, elements that are recognized by the SteelArrow WAS engine, are not sent back
to the client browser. Instead they are replaced with their equivalent processing. In the
case of the above mentioned OUTPUT tag, the data value representing the current state of the
PARAM table would replace the <SAOUTPUT VALUE=PARAM[]>
Side Note: Displaying any variable value can be achieved with the <SAOUTPUT> tag.
The [] (square brackets) are used to ouput LIST and TABLE objects, and are not required for other
data types. For STRING, INTEGER, and other primitive data types they are ignored.
SteelArrow supports other server side processing tags that do not produce an output. Since these
tags do not produce output, they can appear anywhere within the SteelArrow script, even before the
<HTML> tag. One such tag is the <SAQUERY> tag. This tag offers a developer
the ability to query server resources, and produces a variable that will contain the result. It does
not produce any output since that can only be achieved with the <SAOUTPUT> tag.
Select the below button to see a simple HTML template. The template contains only 2 SteelArrow tags.
One tag is the comment specifier <!--- comment ---> and the other is an example of the
<SAOUTPUT> tag. The value output is your current SESSION object.
Right click in the right hand frame when the example is displayed, and select "View Source" if you
do this, you will see how the SteelArrow specific tags have been removed, and replaced with their
associated values (an empty string replaces the SteelArrow comment, and your SESSION table is output
in place of the <SAOUTPUT> tag.
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