JQuery跨域Ajax

我就是我 2022-07-26 04:05 291阅读 0赞

1.前端Js代码

$.ajax({
    						type:"POST",
    						async:false,
    						url:m_BaseUrl+"FindFirstRoomInfoServlet",
    						data:{"roomParent":0},
    						dataType : "jsonp",//数据类型为jsonp  
    				        jsonp: "jsonpCallback",//服务端用于接收callback调用的function名的参数  
    				        success : function(data)
    				        {  
    	        				if(data!="empty")
    							{
    			 				    //var objs=eval("("+data+")");		 				
    			 					$("#roomId").empty();
    			 					$("#roomId").append("<option value=\"\">请选择</option>");
    			          			var dataArray=data.data; 
    			          			
    			 					for(var i=0;i<dataArray.length;i++)
    			 					{
    			 						if(i==0)
    			 						{
    			 							m_IsEnd=dataArray[i].roombelong;
    			 						}
    			 						$("#roomId").append("<option value=\""+dataArray[i].roomid+"\">"+dataArray[i].roomname+"</option>");
    			 					}
    			 					$("#roomId").selectmenu('refresh', true);
    			 					
    		 					}
    		 					else
    		 					{
    		 						$("#roomId").empty();
    			 					$("#roomId").append("<option value=\"\">请选择</option>");
    			 					$("#roomId").selectmenu('refresh', true);
    		 					}
    		        		}
    					});

2.后台Servlet代码

json返回到前端时，加一个jsonpCallback 名称加在json返回值的前面，json字符串用括号括起来

public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException
        {
            request.setCharacterEncoding("UTF-8");
            response.setContentType("text/html;charset=utf-8");
            response.setHeader("Pragma", "No-cache");
            response.setHeader("Cache-Control", "no-cache");
            response.setDateHeader("Expires", 0);
            
            String sRoomParent = request.getParameter("roomParent") == null ? "0" : request.getParameter("roomParent");
            try
            {
                int iRoomParent = Integer.parseInt(sRoomParent);
                CommUseImp comm = new CommUseImp();
                String sRoomInfo = comm.findRoomInfo(iRoomParent);
                
                if (StringUtils.isNotEmpty(sRoomInfo))
                {
                    
                    //System.out.println(sRoomInfo);
                    JSONObject json = new JSONObject(sRoomInfo);
                    
                    org.json.JSONArray jsonArray = json.getJSONArray("data");
                    
                    PrintWriter out = response.getWriter();
                    String jsonpCallback = request.getParameter("jsonpCallback");//客户端请求参数  
                    out.println(jsonpCallback + "(" + json.toString() + ")");//返回jsonp格式数据  
                    out.flush();
                    out.close();
                }
                else
                {
                    PrintWriter out = response.getWriter();
                    out.write("empty");
                    out.close();
                }
                
            }
            catch (Exception e)
            {
                
                e.printStackTrace();
            }
            
        }