struts2 消息提示或错误提示

this .addActionError(
" actionError!
" );

this .addActionMessage(
" actionMessage!
" );

this .addFieldError(
" field
" , "
fieldError "
);

this .addFieldError(
" field2
" , "
fieldError2 "
);

>>jsp中调用

<%@taglib prefix="s" uri="/struts-tags"%>

<s:actionerror />

<s:fielderror>

　　 <s:param>field</s:param>

　　　<s:param>field2</s:param>

</s:fielderror>

或

<s:fielderror>

　　　 <s:param value="%{'field'}" />

　　　 <s:param value="%{'field2'}" />

</s:fielderror>

< s:actionmessage
/>

下面给出一段代码,帮助大家理解,这里只写了关键代码.
1. Action 类中的部分代码:

ActionMessages ams = new ActionMessages();

ams.add(ActionMessages.GLOBAL_MESSAGE,
new ActionMessage("addMessages : global message" ,false ));

ams.add("error" ,new ActionMessage("addMessages : error message" ,false ));

ams.add("info" ,new ActionMessage("addMessages : info message" ,false ));

this .addMessages(httpServletRequest,ams);

ActionMessages errorMessage
= new ActionMessages();

errorMessages.add(ActionMessages.GLOBAL_MESSAGE,
new ActionMessage("addErrors : global message" ,false ));

errorMessages.add("error" ,
new ActionMessage("addErrors : error message" ,false ));

errorMessages.add("info" ,new ActionMessage("addErrors : info message" ,false ));

this .addErrors(httpServletRequest,errorMessages);

2. JSP文件中的部分代码:

< html:messages
id ="message"
>

< bean:write
name ="message"
/>

< br
/>

</
html:messages >

<!-- 上面代码的输出结果:

addErrors : global message

addErrors : error message

addErrors : info message

-->

< html:messages
id ="message"
property ="info"
>

< bean:write
name ="message"
/>
<br />

</
html:messages >

<!-- 这段代码的输出结果为:

addErrors : info message

-->

< html:messages
id ="message"
message ="true"
>

< bean:write
name ="message"
/>
<br />

</
html:messages >

<!-- 这段代码的输出结果:

addMessages : global message

addMessages : error message

addMessages : info message

-->

< html:messages
id ="message"
message ="true"
property ="info"
>

< bean:write
name ="message"
/>
<br />

</
html:messages >

<!-- 这段代码的输出结果为:

addMessages : info message

-->