struts2标签

一、通用标签

1、property

  

 
 

Name

Required

Default

Evaluated

Type

Description

default false   false String The default value to be used if value attribute is null
escape false true false Boolean Deprecated. Use 'escapeHtml'. Whether to escape HTML
escapeCsv false false false Boolean Whether to escape CSV (useful to escape a value for a column)
escapeHtml false true false Boolean Whether to escape HTML
escapeJavaScript false false false Boolean Whether to escape Javascript
escapeXml false false false Boolean Whether to escape XML
value false <top of stack> false Object Value to be displayed

  <s:property value="username" />输出变量名为username的变量,value中的值会被当成ognl表达式输出

  <s:property value="'username'" />输出username,加了单引号不会当成ognl表达式而是当成字符串输出

  <s:property value="admin" default="xiaoming" /> 输出变量名为admin的值,如果没有则默认为xiaoming

  <s:property value="'<br/>'" escape="false" />

2、set

 
 

Name

Required

Default

Evaluated

Type

Description

id false   false String Deprecated. Use 'var' instead
name false   false String Deprecated. Use 'var' instead
scope false action false String The scope in which to assign the variable. Can be applicationsessionrequestpage, or action.
value false   false String The value that is assigned to the variable named name
var false   false String Name used to reference the value pushed into the Value Stack

  <s:set var="username" value="xiaomi" />默认为request和ActionContext

  从request取值<s:property value="#request.username" />(debug标签可能在username还未放到request中时就已经形成了,所以有时候会看不到)

  从ActionContext取值<s:property value="#username" />

  

  设定范围<s:set var="username" value="xiaomi" scope="session" />

  从设定范围取值<s:property value="#session.username" />

3、bean

 
 

Name

Required

Default

Evaluated

Type

Description

id false   false String Deprecated. Use 'var' instead
name true   false String The class name of the bean to be instantiated (must respect JavaBean specification)
var false   false String

Name used to reference the value pushed into the Value Stack

    调用无参构造函数构造一个User类示例:xiaomi<s:bean name="cn.orlion.model.User var="xiaomi"></s:bean>

  调用无参构造函数构造一个User类示例:dami,初始化name为dami

  <s:bean name="cn.orlion.model.User var="dami">

    <s:param name="name" value="'dami'"></s:param> 这里value中的值必须要用单引号引起来,不然会被当成ognl表达式!!!

  </s:bean>

4、include

 
 

Name

Required

Default

Evaluated

Type

Description

value true   false String The jsp/servlet output to include

 

  <s:include value="/index.jsp" />

 

  <s:include value="/index.jsp">

    <s:param name="param1">value1</s:param>    (value会被当成字符串处理)

    <s:param name="param2">value2</s:param>

  </s:include>

  包含动态文件:

  <s:set name="url" value="'/index.jsp'" />

  <s:include value="%{#url}" />

5、param

 
 

Name

Required

Default

Evaluated

Type

Description

name false   false String Name of Parameter to set
suppressEmptyParameters false false false Boolean Whether to suppress empty parameters
value false The value of evaluating provided name against stack false String Value expression for Parameter to set

 

可以:<s:param name="param1" value="value1" />这里value1会被当成ognl表达式

也可以:<s:param name="param1" />value1</s:param>这里value1会被当成字符串

6、debug

不多作介绍

二、控制标签

1、if elseif else

  <s:if test="%{false}">

    <p>1</p>

  </s:if>

  <s:elseif test="%{true}">

    <p>2</p>

  </s:elseif>

  <s:else>

    <p>3</p>

  </s:else>

 

2、iterator

Name

Required

Default

Evaluated

Type

Description

begin false 0 false Integer if specified the iteration will start on that index
end false Size of the 'values' List or array, or 0 if 'step' is negative false Integer if specified the iteration will end on that index(inclusive)
id false   false String Deprecated. Use 'var' instead
status false false false Boolean If specified, an instanceof IteratorStatus will be pushed into stack upon each iteration
step false 1 false Integer if specified the iteration index will be increased by this value on each iteration. It can be a negative value, in which case 'begin' must be greater than 'end'
value false   false String the iteratable source to iterate over, else an the object itself will be put into a newly created List
var false   false String Name used to reference the value pushed into the Value Stack

 

 遍历集合:(输出123)

  <s:iterator value="{1,2,3}">

    <s:property/>

  </s:iterator>

自定义变量:(输出ABC)从集合中迭代取出赋值给val

  <s:iterator value="{'a',  'b' , 'c'}" var="val">

    <s:property value="#val.toUpperCase()"/>

  </s:iterator>

使用status:

  <s:iterator value="{'a' , 'b'  , 'c'}" status="status">

    <s:property/>

    遍历过的元素的总数<s:property value="#status.count" />

    当前元素的索引<s:property value="#status.index" />

    当前是偶数<s:property value="#status.even" />

    当前是奇数<s:property value="#status.odd" />

    是否是第一个元素<s:property value="#status.first" />

    是否是最后一个元素<s:property value="#status.last" />

  </s:iterator>

 

遍历map

  <s:iterator value="#{1:'a' , 2:'b' , 3:'c'}">

    <s:property value="key" /> | <s:property value="value" />

  </s:iterator>

 

  <s:iterator value="#{1:'a' , 2:'b' , 3:'c'}" var="val">

    <s:property value="#val.key" /> | <s:property value="#val.value" />

  </s:iterator>

3、subset

Name

Required

Default

Evaluated

Type

Description

count false   false Integer Indicate the number of entries to be in the resulting subset iterator
decider false   false org.apache.struts2.util.SubsetIteratorFilter.Decider Extension to plug-in a decider to determine if that particular entry is to be included in the resulting subset iterator
id false   false String Deprecated. Use 'var' instead
source false   false String Indicate the source of which the resulting subset iterator is to be derived base on
start false   false Integer Indicate the starting index (eg. first entry is 0) of entries in the source to be available as the first entry in the resulting subset iterator
var false   false String The name to store the resultant iterator into page context, if such name is supplied

三、UI标签

1、theme

主题,默认为xhtml,可以设置为simple/css_html/ajax

struts.xml中<constant name="theme" value="simple" />

posted @ 2015-12-07 22:25  orlion  阅读(349)  评论(0编辑  收藏  举报