
Using ColdFusion components
227
To invoke a method of a component instance using the cfinvoke tag:
1
Create a file named tellTime2.cfc with the following code:
<cfcomponent>
<cffunction name="getLocalTime" access="remote">
<cfreturn TimeFormat(now())>
</cffunction>
<cffunction name="getUTCTime" access="remote">
<cfscript>
serverTime=now();
utcTime=GetTimeZoneInfo();
utcStruct=structNew();
utcStruct.Hour=DatePart("h", serverTime);
utcStruct.Minute=DatePart("n", serverTime);
utcStruct.Hour=utcStruct.Hour + utcTime.utcHourOffSet;
utcStruct.Minute=utcStruct. utcTime.utcMinuteOffSet;
if (utcStruct.Minute LT 10)
utcStruct.Minute = "0" & utcStruct.Minute;
</cfscript>
<cfreturn utcStruct.Hour & ":" & utcStruct.Minute>
</cffunction>
</cfcomponent>
The example defines two component methods:
getLocalTime
and
getUTCTime
.
2
Create a new ColdFusion page, with the following code and save it in the same directory as the
tellTime component:
<!--- Create the component Instance --->
<cfobject component="tellTime2" name="tellTimeComp">
<!--- Invoke the methods --->
<cfinvoke component="#tellTimeComp#" method="getLocalTime"
returnvariable="localTime" >
<cfinvoke component="#tellTimeComp#" method="getUTCTime"
returnvariable="UTCTime" >
<!--- Display the results --->
<h3>Time Display Page</h3>
<cfoutput>
Server's Local Time: #localTime#<br>
Calculated UTC Time: #UTCTime#
</cfoutput>
This example modifies and expands the example from the
“Invoking component methods
transiently using the cfinvoke tag”
section. It uses the
cfobject
tag to create an instance of the
tellTime component and the
cfinvoke
tag to invoke the instance’s
getLocalTime
and
getUTCTime
methods. Unlike the CFC example in
“Invoking component methods transiently
using the cfinvoke tag”
, these methods return a value to the caller, and do not display the results
directly; instead, the calling page displays the returned results.
This example is more modular than the previous example because the CFC contains the
functional logic and returns a result to the calling page, and the calling page displays the results.
This structure separates the logic from the display functions, which usually results in more
reusable code.
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...