防止重复提交:
**1.action类继承 ActionSupport
2.jsp页面上加入 <%@ taglib prefix="s" uri="/struts-tags"/>
3.form 表单中加入 <s:token></s:token>
相当于加入:**
<input type="hidden" name="struts.token.name" value="token" />
<input type="hidden" name="token" value="DFPSPJEZ7DO0LX1VUZZZTC8O14LDJ9OJ" />
struts.xml加入
对insert.action 起到拦截作用
<interceptor-ref name="token">
<param name="includeMethods">insert</param>
</interceptor-ref>
<interceptor-ref name="defaultStack"></interceptor-ref>
<result name="invalid.token">/error.jsp</result>
默认返回值是 invalid.token 会跳转error.jsp