Adobe ColdFusion 8

cfswitch

Description

Evaluates a passed expression and passes control to the cfcase tag that matches the expression result. You can, optionally, code a cfdefaultcase tag, which receives control if there is no matching cfcase tag value.

Category

Flow-control tags

Syntax

<cfswitch 
    expression = "expression">
        one or more cfcase tags
        zero or one cfdefaultcase tags
</cfswitch>

See also

cfcase, cfdefaultcase, cfabort, cfloop, cfbreak, cfexecute, cfexit, cfif, cflocation, cfrethrow, cfthrow, cftry; "cfswitch, cfcase, and cfdefaultcase" in the ColdFusion Developer's Guide

History

ColdFusion 8: Changed the way the ColdFusion parses <cfcase> values. Previously, <cfcase> tags with numeric value dates did not return expected results. For example, <cfcase value="00"> and <cfcase value="0A> were both evaluated to 0. The value "0A" was treated as a date and converted to 0 number of days from 12/30/1899. The value "00" was also evaluated to the value 0. This caused the exception "Context validation error for tag CFCASE. The CFSWITCH has a duplicate CFCASE for value "0.0"." The <cfswitch> tag now returns the expected result.

ColdFusion MX: Changed cfdefaultcase tag placement requirements: you can put the cfdefaultcase tag at any position within a cfswitch statement; it is not required to be the last item.

Attributes

Attribute

Req/Opt

Default

Description

expression

Required

 

ColdFusion expression that yields a scalar value. ColdFusion converts integers, real numbers, Booleans, and dates to numeric values. For example, true, 1, and 1.0 are all equal.

Usage

This tag requires an end tag. All code within this tag must be within a cfcase or cfdefaultcase tag. Otherwise, ColdFusion throws an error.

Use this tag followed by one or more cfcase tags. Optionally, include a cfdefaultcase tag. This tag selects the matching alternative from the cfcase and cfdefaultcase tags, jumps to the matching tag, and executes the code between the cfcase start and end tags.

The cfswitch tag provides better performance than a series of cfif/cfelseif tags, and the code is easier to read.

Example

<!--- 
    This example shows the use of cfswitch and cfcase to 
    exercise a case statement in CFML. 
--->
<cfquery name = "GetEmployees" dataSource = "cfdocexamples">
    SELECT Emp_ID, FirstName, LastName, EMail, Phone, Department
    FROM Employees
</cfquery>

<h3>cfswitch Example</h3>
<!--- By outputting the query and using cfswitch, we classify the 
    output without using a cfloop construct. --->
<p>Each time the case is fulfilled, the specific information is printed; 
if the case is not fulfilled, the default case is output </p> 
<cfoutput query="GetEmployees"> 
<cfswitch expression="#Trim(Department)#"> 
    <cfcase value="Sales"> 
        #FirstName# #LastName# is in <b>sales</b><br><br> 
    </cfcase> 
    <cfcase value="Accounting"> 
        #FirstName# #LastName# is in <b>accounting</b><br><br> 
    </cfcase> <cfcase value="Administration"> 
        #FirstName# #LastName# is in <b>administration</b><br><br> 
    </cfcase> 
    <cfdefaultcase> 
        #FirstName# #LastName# is not in Sales, Accounting, or
            Administration.<br><br>
    </cfdefaultcase> 
</cfswitch> 
</cfoutput>