
Handling exceptions
139
Handling exceptions
ColdFusion provides two statements for exception handling in CFScript:
try
and
catch
. These
statements are equivalent to the CFML
cftry
and
cfcatch
tags.
Note:
This section does not explain exception-handling concepts. For a discussion of exception
handling in ColdFusion, see
Chapter 14, “Handling Errors,” on page 285
.
Exception handling syntax and rules
Exception-handling code in CFScript has the following format:
try {
Code where exceptions will be caught
}
catch(
exceptionType exceptionVariable
) {
Code to handle exceptions of type exceptionType
that occur in the try block
}
...
catch(
exceptionTypeN exceptionVariableN
) {
Code to handle exceptions of type
exceptionTypeN that occur in the try block
}
Note:
In CFScript,
catch
statements follow the
try
block; you do not put them inside the
try
block.
This structure differs from that of the
cftry
tag, which must include the
cfcatch
tags in its body.
When you have a
try
statement, you must have a
catch
statement. In the
catch
block, the
exceptionVariable
variable contains the exception type. This variable is the equivalent of the
cfcatch
tag
cfcatch.Type
built-in variable.
Exception handling example
The following code shows exception handling in CFScript. It uses a
CreateObject
function to
create a Java object. The catch statement executes only if the
CreateObject
function generates an
exception. The displayed information includes the exception message; the except.Message variable
is the equivalent of calling the Java
getMessage
method on the returned Java exception object.
<cfscript>
try {
emp = CreateObject("Java", "Employees");
}
catch(Any excpt) {
WriteOutput("The application was unable to perform a required
operation.<br>
Please try again later.<br>If this problem persists, contact
Customer Service and include the following information:<br>
#excpt.Message#<br>");
}
</cfscript>
Содержание ColdFusion MX
Страница 1: ...Developing ColdFusion MX Applications...
Страница 22: ...22 Contents...
Страница 38: ......
Страница 52: ...52 Chapter 2 Elements of CFML...
Страница 162: ......
Страница 218: ...218 Chapter 10 Writing and Calling User Defined Functions...
Страница 250: ...250 Chapter 11 Building and Using ColdFusion Components...
Страница 264: ...264 Chapter 12 Building Custom CFXAPI Tags...
Страница 266: ......
Страница 314: ...314 Chapter 14 Handling Errors...
Страница 344: ...344 Chapter 15 Using Persistent Data and Locking...
Страница 349: ...About user security 349...
Страница 357: ...Security scenarios 357...
Страница 370: ...370 Chapter 16 Securing Applications...
Страница 388: ...388 Chapter 17 Developing Globalized Applications...
Страница 408: ...408 Chapter 18 Debugging and Troubleshooting Applications...
Страница 410: ......
Страница 426: ...426 Chapter 19 Introduction to Databases and SQL...
Страница 476: ...476 Chapter 22 Using Query of Queries...
Страница 534: ...534 Chapter 24 Building a Search Interface...
Страница 556: ...556 Chapter 25 Using Verity Search Expressions...
Страница 558: ......
Страница 582: ...582 Chapter 26 Retrieving and Formatting Data...
Страница 668: ......
Страница 734: ...734 Chapter 32 Using Web Services...
Страница 760: ...760 Chapter 33 Integrating J2EE and Java Elements in CFML Applications...
Страница 786: ...786 Chapter 34 Integrating COM and CORBA Objects in CFML Applications...
Страница 788: ......
Страница 806: ...806 Chapter 35 Sending and Receiving E Mail...