检查 Dobby 是否有主人,其文本值不为空
XML
<Dobby>
<address>Hogwartz</address>
<master></master>
<colour>wheatish</colour>
<side>all good</side>
</Dobby>
XPATH
boolean(/Dobby/master/text())
要么
string(/Dobby/master) != ''
OUTPUT
false
XML
<Dobby>
<address>Hogwartz</address>
<master></master>
<colour>wheatish</colour>
<side>all good</side>
</Dobby>
XPATH
boolean(/Dobby/master/text())
要么
string(/Dobby/master) != ''
OUTPUT
false