JSON string sort problems encountered in reverse date

<Scripttype= "Text/javascript" >        varStrjson= [        {                        "Commentid": 30000000079,            "Commenttext": "111",            "UserName": "Anonymous User",            "Submittime": "2015-02-05 17:40"        },     {         "Commentid": 30000023628,         "Commenttext": "222 Can we finish the game?",         "userdisplayaddress": "Shanghai Zhabei",         "Submittime": "2015-06-16 17:00"     },   {       "Commentid": 30000023627,       "Commenttext": "333 's not over yet?",       "Submittime": "2015-06-16 17:00"   }]; //var obj = json.parse (Strjson);        functionGetsortfun (Order, sortby) {varOrdalpah=(Order== 'ASC') ? '>' : '<'; varSortfun= NewFunction ('a', 'b', 'return a.' +SortBy+Ordalpah+ 'B.' +SortBy+ '? 1:-1');//using the function constructor, the last parameter is considered a function body, and the preceding parameter enumerates the parameters of the new function.             //var sortfun = function (A, B) {//Consider why the function cannot replace the above operation.             //return A.sortby + Ordalpah + b.sortby? 1:-1;            //}            returnSortfun; } strjson.sort (Getsortfun ('desc', 'Submittime')); //alert (json.stringify (Strjson));document.write (Json.stringify (Strjson))</Script>

JSON string sort problems encountered in reverse date