cftry/cfcatch issue

"Errors" is the generic name but, technically, there is a distinction between the categories of error. The two categories that concern us here are "Syntax errors" and "Exceptions".

Coldfusion, like most programming languages, begins by parsing the code. If it finds a mistake in the Coldfusion syntax or grammar, it will stop and signal it to you. Those are errors which the parser identifies as "bad Coldfusion" or "non-Coldfusion". An example is <cfsat x=1>. Coldfusion doesn't continue past the first syntax error. No need.

Coldfusion would only execute a piece of code if it found no syntax errors in it during the parsing phase. "Exception" is the general name for an error that occurs during the execution phase. An example is <cfset x=1/0>. Though it is division by zero, the statement has correct Coldfusion syntax.

The try-catch mechanism is meant to trap exceptions. As such, it only comes into effect during code execution.

Your code contains two syntax errors. First, <cfset 11 = 1> is not a valid Coldfusion statement. Second, "2/31/06" is not a valid date object and cannot be cast into one. Coldfusion will therefore not even execute the code, and so the try-catch will not have the opportunity to run.

An example of code that will throw and catch exceptions: