Jsp IfÌõ¼þÅжÏÎÊÌâ. - Java / Web ¿ª·¢

ÐÂÊÖ:
tomcat+struts 2.0
jsp Ò³ÃæÖ±½Ó¹ØÁªmodel
ÏÖÔÚÐèÒª¸ù¾Ýmodel(admin)ÀïÃæµÄÒ»¸öitem(id),ÅжÏjspÒ³Ãæ³öÏÖµÄÄÚÈÝ.
´ó¸ÅÁ÷³Ì:
...
<table>
<tr>
<td>

<s:if admin.id is null> ---Õâ¸öµØ·½²»ÖªµÀÔõôд , admin.idÊÇStringÀàÐÍ
<s:text name="admin.name"></s:text>
</s:if>
<s:else>
<s:text name="admin.title"></s:text>
</s:else>

</td>
</tr>
</table>
...

---

<s:if test="#admin.name == null">

---

4. <s:if test="#request.admin.id == null"> 

---

ллlsÁ½Î»µÄ»Ø¸´.¾­¹ý²âÊÔ.
1. <s:if test="admin.id == null"> 

2. <s:if test="%{admin.id == null}"> 

3. <s:if test="%{#request.admin.id == null}"> 

4. <s:if test="#request.admin.id == null"> 
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Java code:

1. <s:if test="admin.id == null">

2. <s:if test="%{admin.id == null}">

3. <s:if test="%{#request.admin.id == null}">

4. <s:if test="#request.admin.id == null">

---

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