Post JSON
var params = {
"param1" : "value1"
};
$.ajax({
type : "post",
url : "https://www.xxx.com/url",
data : JSON.stringify(params),
contentType : 'application/json; charset=utf-8',
dataType : "json",
success : function(result, dataType) {xxx(result,dataType);},
complete : function(json_data) {},
error : function(result, dataType){alert("Error");}
});