Hide/Remove dialogbox close button in title

closeOnEscape: false,
open: function (event, ui) { $(".ui-dialog-titlebar-close").hide(); },

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$("#popUpOne").dialog({
                autoOpen: false,
                height: 660,
                width: 740,
                modal: true,
                closeOnEscape: false,
                open: function (event, ui) { $(".ui-dialog-titlebar-close").hide(); },
                buttons: {
                    "SAVE": function () {
                        SaveFunction();
                    },
                    CANCEL: function () {
                        $(this).dialog("close");
                    }
                },
                close: function () {
                    allFields.val("").removeClass("ui-state-error");
                }
            });