ext 、ajax和servlet结合的一个小例子

extjs:

Ext.onReady(function(){
    Ext.get("btnSubmit").on('click',function(){
        var content =Ext.get("com_content").getValue();
        if(content==""){
            Ext.MessageBox.alert("内容不能为空！");
        }
        else{
            Ext.Ajax.request({
            url:'MessageBoxServlet',
            params: {content :content} ,
            Method:"post",
            success: function(response){
                //var message = request.responseText;
                var message = response.responseText;
                Ext.get("CommentList").dom.innerHTML=response.responseText;
                //Ext.MessageBox.alert("信息",message);
            },
            failure: function(response){
                Ext.MessageBox.alert("错误！"+response.status);
            }
            });
        }
    })    
})

servlet:

public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setCharacterEncoding("utf-8");
        String content = request.getParameter("content");
        
        //response.getWriter().write(content);
        PrintWriter out = response.getWriter();
        out.print(content);
        out.flush();
        out.close();
    }