struts整合jQuery与ajax

首先来一个测试ajax的按钮:

<input type="button" value="ajax" id="test" onclick="testajax()">

然后为其注册ajax方法:

<script type="text/javascript">
    
    function testajax() {
//        var ctx = ${pageContext.request.contextPath};
        alert("in");
         $.ajax({
             url : '/testStruts/ajax.action',
             data : { 'photourl' : 'test'},
             type : 'POST',
             dataType : 'html',
             success : function(json) {
             alert(json);
             },
             error : function(xhr, status) {
                 alert('更新错误！');
             },
             });

    }
    
</script>

struts.xml的配置:

<!-- 注意,result不需要配置name属性-->

<action name="ajax" class="chj.abc.ajaxAction" method="ajax">
            <result >
                /ajax.jsp
            </result>
 </action>

Action:

package chj.abc;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;


public class ajaxAction extends ActionSupport{
    public String ajax() throws IOException{
        System.out.println("testing ajax.....");
        
        HttpServletRequest request = ServletActionContext.getRequest();
        HttpServletResponse response = ServletActionContext.getResponse();
        // 设置字符集
        response.setContentType("text/plain");// 设置输出为文字流
        response.setCharacterEncoding("UTF-8");
        PrintWriter out = response.getWriter();
        String type=request.getParameter("photourl");//interval
        System.out.println(type);
        out.write("hello world");
            out.flush();
            out.close();

        return null;
    }
}

注意:Action的最后返回的是null