MACROMEDIA COLFUSION MX 7 - INSTALLING AND USING COLDFUSION MX, Reference

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cfthrow 419
Usage
Use this tag within a
cftry
block, to throw an error. The
cfcatch
block can access
accompanying information, as follows:
•
Message, with
cfcatch.message
•
Detail, with
cfcatch.detail
•
Error code, with
cfcatch.errorcode
To get more information, use
cfcatch.tagContext
. This array shows where control switches
from one page to another in the tag stack (for example,
cfinclude
,
cfmodule
).
To display the information displayed by
tagContext
: in the ColdFusion MX Administrator,
Debugging page, select Enable CFML Stack Trace.
Using the object parameter To use this tag with the
object
parameter, you must first use a
cfobject
tag that specifies a valid Java exception class. For example, the following
cfobject
tag
defines an object, obj, of the exception class myException (which you must create in Java):
<cfobject
type="java"
action="create"
class="myException"
name="obj">
If your exception class has constructors that take parameters, such as a message, you can use the
special
init
method to invoke the constructor, as in the following line. If you do not need to
specify any constructor attributes, you can omit this step.
<cfset obj.init("You must save your work before preceding")>
You can then use the, the
cfthrow
statement to throw the exception as follows:
<cfthrow object=#obj#>
For more information on using Java objects in ColdFusion, see Chapter 37, “Integrating J2EE
and Java Elements in CFML Applications” in
ColdFusion MX Developer’s Guide .
Example 1
<h3>cfthrow Example</h3>
<!--- Open a cftry block. --->
<cftry>
<!--- Define a condition upon which to throw the error. --->
<cfif NOT IsDefined("URL.myID")>
<!--- throw the error --->
<cfthrow message = "ID is not defined">
</cfif>
extendedInfo Optional A custom error code that you supply.
object Optional Requires the value of the
cfobject
tag
name
attribute.
Throws a Java exception from a CFML tag.
This attribute is mutually exclusive with all other attributes of
this tag.
Attribute Req/Opt Default Description