ColdFusion Developer's Guide

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Handling missing template errors
Missing template errors occur when ColdFusion receives an HTTP request for a page ending
in .cfm that it cannot find. You can create your own missing template error page to present
application-specific information or provide an application-specific appearance. You specify
the missing template error page on the Administrator Settings page.
The missing error page can use CFML tags and variables. In particular, you can use the
CGI.script_name variable in text such as the following to identify the requested page:
The page #Replace(CGI.script_name, "/", "")# is not
available.
Make sure that you entered the page correctly.
(In this code, the Replace function removes the leading slash sign from the script name to
make the display more friendly.)
Handling form field validation errors
When you use server-side form field validation, the default validation error message describes
the error cause plainly and clearly. However, you might want to give the error message a
custom look or provide additional information such as service contact phone numbers and
addresses. In this case, use the cferror tag with the Validation attribute in the
Application.cfc initialization code or on the Application.cfm page to specify your own
validation error handler. The section “Example of a validation error page” on page 376
provides an example of such a page. You can also put form field validation error handling code
in the Application.cfc onError method.
Handling compiler exceptions
You cannot handle compiler exceptions directly on the page where they occur, because the
exception is caught before ColdFusion starts running the page code. You should fix all
compiler exceptions as part of the development process. Use the reported error message and
the code debugging techniques discussed in Chapter 19, “Debugging and Troubleshooting
Applications” to identify and correct the cause of the error.
Compiler exceptions that occur on pages you access by using the cfinclude or cfmodule tags
can actually be handled as runtime errors by surrounding the cfinclude or cfmodule tag in a
cftry block. The compiler exception on the accessed page gets caught as a runtime error on
the base page. However, you should avoid this "solution" to the problem, as the correct
method for handling compiler errors is to remove them before you deploy the application.
Determining error-handling strategies 371