User Guide

468 Chapter 3: ColdFusion Functions
Evaluate
Description
Evaluates one or more string expressions, dynamically, from left to right. (The results of an
evaluation on the left can have meaning in an expression to the right.) Returns the result of
evaluating the rightmost expression.
Returns
An object; the result of the evaluation(s).
Category
Dynamic evaluation functions
Function syntax
Evaluate(string_expression1 [, string_expression2 [, … ] ] )
See also
DE, IIf
Parameters
Usage
String expressions can be complex. If a string expression contains a single or double quotation
mark, it must be escaped.
This function is useful for forming one variable from multiple variables. For example, to reference
a column of the query qNames with a variable,
var, using an index value to traverse rows, you
could use the following code:
<cfset var=Evaluate("qNames.#colname#[#index#]")>
For more information, see Chapter 4, “Using Expressions and Pound Signs,” in Developing
ColdFusion MX Applications.
Example
<!--- This shows the use of DE and Evaluate --->
<h3>Evaluate Example</h3>
<cfif IsDefined("FORM.myExpression")>
<h3>The Expression Result</h3>
<cftry>
<!--- Evaluate the expression --->
<cfset myExpression = Evaluate(FORM.myExpression)>
<!--- Use DE to output the value of the variable, unevaluated --->
<cfoutput>
<I>The value of the expression #Evaluate(DE(FORM.MyExpression))#
is #MyExpression#.</I>
</cfoutput>
...
Parameter Description
string_expression1,
string_expression2...
Expressions to evaluate