spring3 mvc 回来的json格式数据jquery解析不了

spring3 mvc 返回的json格式数据jquery解析不了
用ajax提交的请求返回的json数据data：

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来自网页的消息

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{"description":null,"result":{"address":null,"id":10,"email":"chris.zhang@foxmail.com","pwd":"1","loginName":"啊啊","nickName":"111搜索","headPicPath":null,"mobilePhone":"2","deskPhone":null,"vid":null,"birthday":null,"sex":null,"lastName":null,"firstName":null,"cityId":0,"districtId":0,"lasLoginIp":null,"creatTime":1367482926000,"userType":null,"userStatus":null,"lasLogiClient":null,"lasLogiTime":1367481551000},"isSuccessMessage":1,"statusCode":220000,"sendDetail":null}

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确定   

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可以直接alert出来，以上是alert(data)的结果
可是为什么alert(data.result)就是undefined了？
------解决方案--------------------

---------------------------//去掉

来自网页的消息//去掉

---------------------------/去掉

{"description":null,"result":{"address":null,"id":10,"email":"chris.zhang@foxmail.com","pwd":"1","loginName":"啊啊","nickName":"111搜索","headPicPath":null,"mobilePhone":"2","deskPhone":null,"vid":null,"birthday":null,"sex":null,"lastName":null,"firstName":null,"cityId":0,"districtId":0,"lasLoginIp":null,"creatTime":1367482926000,"userType":null,"userStatus":null,"lasLogiClient":null,"lasLogiTime":1367481551000},"isSuccessMessage":1,"statusCode":220000,"sendDetail":null}

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确定   //去掉

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你这压根就不是JSON字符串。把上面标注的全部去掉。
------解决方案--------------------
加上dataType:'json'，jquery应该按照文本来处理了，没有处理成json对象