Adobe Dreamweaver CC 2014 v.13 - Manual (Page 549)

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server behavior, the code you write must be valid ColdFusion code that runs on a ColdFusion application server.
You can create the code blocks either directly in the Server Behavior Builder, or you can copy and paste the code from other sources. Each code
block you create in the Server Behavior Builder must be a single tag or script block. If you must insert multiple tag blocks, split them into separate
code blocks.
Conditions in code blocks
Dreamweaver lets you develop code blocks that incorporate control statements that execute conditionally. The Server Behavior Builder uses if,
elseif, and else statements, and may also contain server behavior parameters. This enables you to insert alternate text blocks based on the values
of OR relationships among server behavior parameters.
The following example shows the if, elseif, and else statements. The square brackets ([ ]) denote optional code and the asterisk (*) denotes zero or
more instances. To execute a portion of a code block or the entire code block only if a certain condition or conditions apply, use the following
syntax:
<@ if (expression1) @> conditional
text1[<@ elseif (expression2) @> conditional text2]*[<@ else @>
conditional text3]<@ endif @>
Condition expressions can be any JavaScript expression that can be evaluated using the JavaScript eval() function, and may include a server
behavior parameter marked by @@’s. (The @@’s distinguish the parameter from JavaScript variables and keywords.)
Effectively using conditional expressions
When using if, else, and elseif directives within the insertText XML tag, the participant text is preprocessed to resolve the if directives and to
determine which text to include in the result. The if and elseif directives take the expression as an argument. The condition expression is the same
as that for JavaScript condition expressions, and can also contain server behavior parameters. Directives such as this allow you to choose
between alternative code blocks based on the values of, or relationships between, server behavior parameters.
For example, the following JSP code comes from a Dreamweaver server behavior that uses a conditional code block:
@@rsName@@.close();
<@ if (@@callableName@@ != '') @>
@@callableName@@.execute();
@@rsName@@ = @@callableName@@.getResultSet();<@ else @>
@@rsName@@ = Statement@@rsName@@.executeQuery();
<@ endif @>
@@rsName@@_hasData = @@rsName@@.next();
The conditional code block starts with <@ if (@@callableName@@ != '') @> and ends with <@ endif @>. According to the code, if the user
enters a value for the @@callableName@@ parameter in the server behavior's Parameter dialog box—in other words, if the
@@callableName@@ parameter value is not null, or (@@callableName@@ != '')—then the conditional code block is replaced with the following
statements:
@@callableName@@.execute();
@@rsName@@ = @@callableName@@.getResultSet();
Otherwise, the code block is replaced with the following statement:
@@rsName@@ = Statement@@rsName@@.executeQuery();
Positioning a code block
When you create code blocks using the Server Behavior Builder, you must specify where to insert them in the page’s HTML code.
For example, if you insert a code block above the opening tag, you must then specify the code block’s position relative to other tags,
scripts, and server behaviors in that section of the page’s HTML code. Typical examples include positioning a behavior either before or after any
recordset queries that might also exist in the page code above the opening tag.
When you select a positioning option from the Insert Code pop-up menu, the options available in the Relative Position pop-up menu change to
provide relevant options for that part of the page. For example, if you select Above The Tag In The Insert Code pop-up menu, the
positioning options available in the Relative Position pop-up menu reflect choices relevant for that part of the page.
The following table shows the code block insert options, and the relative positioning options available for each:
Insert Code options Relative position options
Above the Tag
At the beginning of the file
Just before the recordsets
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