WebWork2 UI标签

webwork2使用OGNL（Object-Graph Navigation Language）与界面元素绑定，OGNL包含一个根对像（OGNLValueStack）和其他Map类型的上下文对像。OGNL可以直接访问对像属性，访问上下文Map对像要加#，根对像不需要。

       |--request
                     |
                     |--application
                     |
       context map---|--OgnlValueStack(root)
                     |
                     |--session
                     |
                     |--attr
                     |
                     |--parameters

1.访问根对像
<ww: property value="myBean.myProperty"/>
2.访问 session
ActionContext.getContext().getSession().put("mySessionPropKey", mySessionObject);
<ww:property value="#session.mySessionPropKey"/> or
<ww:property value="#session['mySessionPropKey']"/> or
<ww:property value="#attr.mySessionPropKey"/>

3.加载list到select框

<ww:select label="label" name="name" list="{'name1','name2','name3'}" value="%{'name2'}" />
<ww:select label="label" name="name" list="#{'foo':'foovalue', 'bar':'barvalue'}" />

4.条件语句

<ww:if test="'foo' in {'foo','bar'}">
   muhahaha
</ww:if>
<ww:else>
   boo
</ww:else>

<ww:if test="'foo' not in {'foo','bar'}">
   muhahaha
</ww:if>
<ww:else>
   boo
</ww:else>
<ww:if test="%{false}">
    <div>Will Not Be Executed</div>
 </ww:if>
	<ww:elseif test="%{true}">
    <div>Will Be Executed</div>
 </ww:elseif>
 <ww:else>
    <div>Will Not Be Executed</div>
 </ww:else>

5.List合并

public class AppendIteratorTagAction extends ActionSupport {

private List myList1;
private List myList2;
private List myList3;


public String execute() throws Exception {

	myList1 = new ArrayList();
	myList1.add("1");
	myList1.add("2");
	myList1.add("3");

	myList2 = new ArrayList();
	myList2.add("a");
	myList2.add("b");
	myList2.add("c");

	myList3 = new ArrayList();
	myList3.add("A");
	myList3.add("B");
	myList3.add("C");

	return "done";
}

public List getMyList1() { return myList1; }
public List getMyList2() { return myList2; }
public List getMyList3() { return myList3; }

<ww:append id="myAppendIterator">
	<ww:param value="%{myList1}" />
	<ww:param value="%{myList2}" />
	<ww:param value="%{myList3}" />
</ww:append>

<ww:iterator value="%{#myAppendIterator}">
	<ww:property />
</ww:iterator>

http://www.opensymphony.com/webwork/wikidocs/Tags.html