canDeactivate方法中的MessageBox在Firefox 25.0中引发错误

Question

This fails in Firefox 25.0 but works without problems in Chrome and IE 11:

 var canDeactivate = function () {
    if (hasChanges()) {
        console.log(customer().CustomerID() < 0);
        var msg = customer().CustomerID() < 0 ?
            'Are you sure you want to discard the customer - "' + customer().CustomerName() + '" ?' :
            'Are you sure you want to discard the changes\n for the the customer - "' + customer().CustomerName() + '" ?';
        var title = 'Confirm navigation';
        return app.showMessage(msg, title, ['Yes', 'No'])
            .then(confirmDelete);

        function confirmDelete(selectedOption) {
            if (selectedOption === 'Yes') {
                return true;
            }
            else {
                return false;
            }
        }
    }
    else {
        return true;
    }
};

In Firefox 25.0 it throws a ReferenceError before it evaluates the response from the message box and it is canceling the navigation without calling the function confirmDelete .

What is the problem?

Answer 1

在return语句解决此问题之前，声明function confirmDelete() {...} 。