Evaluating XPath Expresssions

XPath	Result of XPath Evaluation
if (exists(/FitnessCenter/Member[3])) then 'There is a 3rd Member' else 'Error! No 3rd Member'	There is a 3rd Member
if (exists(/FitnessCenter/Member[99])) then 'There is a 99th Member' else 'Error! No 99th Member'	Error! No 99th Member
exists(/FitnessCenter/Member[3])	true
exists(/FitnessCenter/Member[99])	false
exists(())	false

The XML Document

<FitnessCenter>
        <Member id="1" level="platinum">
                <Name>Jeff</Name>
                <Phone type="home">555-1234</Phone>
                <Phone type="work">555-4321</Phone>
                <FavoriteColor>lightgrey</FavoriteColor>
                <MembershipFee>340</MembershipFee>
        </Member>
        <Member id="2" level="gold">
                <Name>David</Name>
                <Phone type="home">383-1234</Phone>
                <Phone type="work">383-4321</Phone>
                <FavoriteColor>lightblue</FavoriteColor>
                <MembershipFee>500</MembershipFee>
        </Member>
        <Member id="3" level="platinum">
                <Name>Roger</Name>
                <Phone type="home">888-1234</Phone>
                <Phone type="work">888-4321</Phone>
                <FavoriteColor>lightyellow</FavoriteColor>
                <MembershipFee>340</MembershipFee>
        </Member>
</FitnessCenter>