| If Only... |
The first - and simplest - decision-making routine is the "if" statement, which generally looks like this:
The "condition" here refers to a conditional expression, which evaluates to either true or false.
Let's look at a piece of code to understand this better. Here's a DTML Method named "ifOnly", created in the same "DTML Basics" folder I used last time.
<p>Variable "id" exists and has the value <dtml-var id>.</p>
<p>Variable "myName" exists and has the value "<dtml-var myName>".</p>
Now, when you view the output of this Method, you should see the following:
''.preg_replace(array('/ /', '/ /'), array(' ', ' '), '
Variable "id" exists and has the value DTML Basics.
If you take a close look at the code above, you'll see that it includes two "if" statements; however, only one is displayed in the output. This is because the first statement evaluated to a true value, because the variable "id" exists and has a value (the name of the container within which the DTML Method is stored). However, the second DTML variable "myName" does not exist. As a result, the corresponding "if" statement evaluates as false, and so, the text enclosed within the <dtml-if> block is not displayed.
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