Struts2 's s:iterator can traverse any array in the data stack, the collection and so on the following simple demo:
The S:iterator tag has 3 properties:
Value: The collection that is iterated
ID: The ID of the element within the specified collection
The index of the status Iteration element 1:jsp the page definition element array or list
< S:iterator value= "{' 1 ', ' 2 ', ' 3 ', ' 4 ', ' 5 '}" id= ' number ' >
<s:property value= ' number '/>a
</s:iterator>
Printing result: 1a2a3a4a5a 2: Usage of index
If status is specified, each iteration of the data has an instance of Iteratorstatus, and it has the following methods
int GetCount () returns several elements of the current iteration
int GetIndex () returns the current element index
Boolean IsEven () of course the index is even
Boolean IsFirst () whether the first element is currently
Boolean islast ()
Boolean isodd () whether the current element index is odd < S:iterator value= "{' A ', ' B ', ' C '}" id= ' char ' status= ' st ' >
<s:if test= "#st. Even ">
The index is now an odd number: <s:property value= ' #st. Index '/>
</s:if>
Current element value: <s:property value= ' char '/>
</s:iterator>
3: Traverse Map
Value can be defined directly as: value= "#{" 1 ":" A "," 2 ":" B "}"
Each element is well separated. The key and the value colon are separated between elements
Value can also be a Java.util.Map object inside the data stack
The traversal is written as follows: < S:iterator value= "map" id= "id" status= "st" >
Key: <s:property value= ' key '/>
Value:<s:property vlaue= ' value '/>
</s:iterator>
Of course, both key and value can make Java Object 3: traverse the data stack. Simple List class,
List<attr>
Class Attr{string Attrname; String Getattrname () {return "123";}} < s:iterator value= "label" id= "id" >
<s:property value= "#id. Attrname"/>
</s:iterator>
Of course value can also be written value= "%{label}" label can have. Operation
The Label property list can be written as value= "%{label.list}" equivalent to: Getlabel (). GetList (); 4: Traversal of 2 lists;
List<attrname> attrn {Color,size,style}
List<attrvalue> ATTRV {Red,20,gay}
The 2 list elements are one by one corresponding, one attrn corresponds to a ATTRV < S:iterator value= "%{attrn}" id= "id" status= "status" >
Index is: <s:property value= ' Status.index '/>
Attrname is: <s:property value= ' id '/> or <s:property value= '%{id} '/>
Attrname is: <s:property value= '%{attrv[#status. index]} '/>
</s:iterator>
