序列表示项目的有序集合,其中项目可以是相似或不同类型.
使用括号内引号或双引号和数字的括号. XML元素也可以用作序列的项目.
let $items := ('orange', <apple/>, <fruit type="juicy"/>, <vehicle type="car">sentro</vehicle>, 1,2,3,'a','b',"abc") let $count := count($items) return <result> <count>{$count}</count> <items> { for $item in $items return <item>{$item}</item> } </items> </result>
<result> <count>10</count> <items> <item>orange</item> <item> <apple/> </item> <item> <fruit type="juicy"/> </item> <item> <vehicle type="car">Sentro</vehicle> </item> <item>1</item> <item>2</item> <item>3</item> <item>a</item> <item>b</item> <item>abc</item> </items> </result>
序列的项目可以使用索引或按顺序逐个迭代值.上面的例子逐个迭代序列的项目.让我们看看另外两种方法.
let $items := (1,2,3,4,5,6) let $count := count($items) return <result> <count>{$count}</count> <items> { for $item in $items[2] return <item>{$item}</item> } </items> </result>
<result> <count>6</count> <items> <item>2</item> </items> </result>
let $items := (1,2,3,4,5,6) let $count := count($items) return <result> <count>{$count}</count> <items> { for $item in $items[. = (1,2,3)] return <item>{$item}</item> } </items> </result>
<result> <count>6</count> <items> <item>1</item> <item>2</item> <item>3</item> </items> </result>