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Used with CFELSE and CFELSEIF, CFIF lets you create simple and compound conditional statements in CFML. The value in the CFIF tag can be any expression.
<CFIF expression>
HTML and CFML tags
<CFELSEIF>
HTML and CFML tags
<CFELSE expression>
HTML and CFML tags
</CFIF>
Note that when testing for the return value of any function that returns a Boolean, you do not need to explicitly define the TRUE condition. The following code uses IsArray as an example:
<CFIF IsArray(myarray)>
When successful, IsArray evaluates to YES, the string equivalent of the Boolean TRUE. This method is preferred over explicitly defining the TRUE condition:
<CFIF IsArray(myarray) IS TRUE>
In addition to using the decision functions in the expression, such as IsArray and IsBoolean, you can also use any of the ColdFusion operators in the expression.
CFML Operators | ||
|---|---|---|
CFML Operator | Alternate | Checks that the right value is |
| IS | EQUAL, EQ | equal to the left value. |
| IS NOT | NOT EQUAL, NEQ | is not equal to the left value. |
| CONTAINS | is contained within the left value. | |
| DOES NOT CONTAIN | is not contained within the left value. | |
| GREATER THAN | GT | is greater than the left value. |
| LESS THAN | LT | is less than the left value. |
| GREATER THAN OR EQUAL | GTE | is greater than or equal to the left value. |
| LESS THAN OR EQUAL | LTE | is less than or equal to the left value. |
Do not substitute an equal sign (=) for the IS operator.
<!--- This example shows the interaction of CFIF, CFELSE,
and CFELSEIF --->
...
<H3>CFIF Example</H3>
<P>CFIF gives us the ability to perform conditional logic
based on a condition or set of conditions.
<P>For example, we can output the list of Allaire departments from the
HRAPP datasource and only display them <B>IF</B>
the location = Cambridge.
<CFQUERY name="getAllaireDepartments" datasource="HRAPP">
SELECT Department_Name, Location
From Departments
</cfquery>
<hr>
<!--- use CFIF to test a condition when outputting a query --->
<P>The following departments are in Cambridge:
<CFOUTPUT QUERY="getAllaireDepartments" >
<CFIF location is "Cambridge">
<BR><Department:</B>#Department_Name#
</CFIF>
</CFOUTPUT>
<CFQUERY name="getAllaireEmployees" datasource="HRAPP">
SELECT Department_Name, Location
From Departments
</cfquery>
<P>If you would like more than one condition to be the case,
you can ask for a list of departments in Cambridge <B>OR</B>
San Francisco. If the department does not meet either condition, you
can use CFELSE to show only the names and cities of the
other departments.
<CFOUTPUT QUERY="getAllaireEmployees">
<CFIF location is "San Francisco" OR location is "Cambridge">
<BR><I>#Department_Name#, #Location#</I>
<CFELSE>
<BR><I>#Department_Name#, #Location#</I>
</CFIF>
</CFOUTPUT>
<!--- use CFIF to specify a conditional choice for multiple
options; also note the nested CFIF --->
<hr>
<P>You can also use CFELSEIF to provide one or more conditions.</P>
<CFOUTPUT QUERY="getAllaireDepartments">
<CFIF location is "San Francisco">
<BR><I>#Department_Name#, #Location#</I>
<CFELSEIF location is "Cambridge">
<BR><I>#Department_Name#, #Location#</I>
<CFELSEIF location is "London">
<BR><I>#Department_Name#, #Location#</I>
<CFELSE>
<BR><I>#Department_Name#, #Location#</I>
</CFIF>
</CFOUTPUT>
<P>For a more complex example of the use of CFIF, see <A
HREF="listcontains.cfm">ListContains Example</A>.</P>
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