Adobe COLDFUSION 9 Manual page 176

DEVELOPING COLDFUSION 9 APPLICATIONS
Building Blocks of ColdFusion Applications
<cftry>
<cfset status = StructNew()>
<cfset myInterest = TotalInterest(Form.Principal, Form.AnnualPercent,
Form.Months, status)>
<cfoutput>
Loan amount: #Form.Principal#<br>
Annual percentage rate: #Form.AnnualPercent#<br>
Loan duration: #Form.Months# months<br>
TOTAL INTEREST: #myInterest#<br>
</cfoutput>
<cfcatch type="InvalidData">
<cfoutput>
#cfcatch.message#<br>
</cfoutput>
</cfcatch>
</cftry>
A user-defined function example
The following simple function takes a principal amount, an annual percentage rate, and a loan duration in months and
returns the total amount of interest paid over the period. You can optionally use the percent sign for the percentage
rate, and include the dollar sign and comma separators for the principal amount.
You could use the
TotalInterest
<cfoutput>
Loan amount: #Form.Principal#<br>
Annual percentage rate: #Form.AnnualPercent#<br>
Loan duration: #Form.Months# months<br>
TOTAL INTEREST: #TotalInterest(Form.Principal, Form.AnnualPercent, Form.Months)#<br>
</cfoutput>
Defining the function using CFScript
<cfscript>
function TotalInterest(principal, annualPercent, months) {
Var years = 0;
Var interestRate = 0;
Var totalInterest = 0;
principal = trim(principal);
principal = REReplace(principal,"[\$,]","","ALL");
annualPercent = Replace(annualPercent,"%","","ALL");
interestRate = annualPercent / 100;
years = months / 12;
totalInterest = principal*(((1+ interestRate)^years)-1);
Return DollarFormat(totalInterest);
}
</cfscript>
Reviewing the code
The following table describes the code:
function in a tag of a form's action page, as follows:
cfoutput
Last updated 8/5/2010
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