logic:equal,logic:present用法
1.
<logic:equal value="a" name="documentContent">顯示</logic:equal>
<logic:equal name="DeliverProveForm" property="userAction" value="create">
如果DeliverProveForm里的屬性userAction的值等於create就執行這兒。
</logic:equal>
2. <logic:present name="tipmsg"> 如果在你的action中設置了tipmsg就執行到這兒。如：request.setAttribute("tipmsg","提示信息") 或session.setAttribute("tipmsg","提示信息") <bean:write name="tipmsg"/> </logic:present>
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標簽<logic:present>的使用
request.getSession().setAttribute("pageBean", pageBean);
request.setAttribute("result", pageBean.getObjList());
在jsp中：
<logic:present name="result">
<logic:iterate id="book" name="result">
<logic:present name="book">
<tr>
<td><bean:write name="book" property="name" /></td>
<td><bean:write name="book" property="author" /></td>
<td><bean:write name="book" property="price" /></td>
</tr>
</logic:present>
</logic:iterate>
</logic:present>
<logic:present name="result" scope="session">
這里有個scope屬性可能是request,session等, name指的是一個對象,可能是javaBean,也可能是集合的對象,整個意思就是就是在scope(session,request) 范圍里面查找name(一個對象)是否存在,相當於一個if()語句.