<li>空字段测试</li><br>
<form action="blankfield.do" method="post">
姓名：<input type="text" name="username"><br>
<input type="submit" value="提交">
</form>
建立一个BlankFieldActionForm接收空字段
package com.bjsxt.struts;
import org.apache.struts.action.ActionForm;
/**
* 测试空字段
* @author Administrator
*
*/
public class BlankFieldActionForm extends ActionForm {
private String username;
private String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
建立Action：
package com.bjsxt.struts;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
/**
* 测试空字段
* @author Administrator
*
*/
public class BlankFieldTestAction extends Action {
@Override
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
return mapping.findForward("success");
}
}
配置：
<action path="/blankfield"
type="com.bjsxt.struts.BlankFieldTestAction"
name="blankFieldForm"
scope="request"
>
<forward name="success" path="/blankfield_success.jsp"/>
</action>
jsp测试页面：
<body>
<%
BlankFieldActionForm form = (BlankFieldActionForm)request.getAttribute("blankFieldForm");
%>
<li>jsp脚本</li><br>
姓名：<%=form.getUsername() %><br>
密码:<%=form.getPassword() %><br>
<p>
<li>el表达式</li><br>
姓名：${blankFieldForm.username }<br>
密码:${blankFieldForm.password }<br>
</body>
在空字段中jsp脚本得到的是null空对象，而el表达式得到的是一个空字符串。