php ajax error (if pure js is used, status 4 cannot be returned)

Recently, when using php + ajax, the same situation as java did not return success or status 4.

Then the reason is very simple. The data returned by using php is not in the standard json format

Please return the json in the standard format! ! !

http://blog.csdn.net/hzz780/article/details/31393513 Modifying js in java returns success

http://blog.csdn.net/hzz780/article/details/ 26611431 In java case, modify java to return success

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